• Skip to primary navigation
  • Skip to main content
  • Skip to primary sidebar
  • Skip to footer
Joy the Baker
Joy the Baker
  • Cookies
  • Bread
  • Cakes
  • Pies
  • Recipes
    • All Recipes
    • Cookies
    • Birthday Cake Recipes
    • Biscuits
    • Muffins
    • Cupcakes
    • Drinks
    • Breakfast
    • Lunch
    • Dinner
    • Fruit
    • Nuts
    • Buttermilk
    • Chocolate
    • Vanilla
    • Holiday
    • Healthy
    • Gluten-Free
    • Vegan
  • Blog
    • Baking 101
    • Tips
    • Beyond the Kitchen
    • Let It Be Sunday!
    • New Orleans
  • Shop

Whole Roasted Onions

January 10, 2015 by Joy the Baker 98 Comments

Jump to Recipe

Whole roasted onions are soft, aromatic, and so delicious that they become a stand-alone side dish! This recipe and these tips will give you the perfect baked onion every single time.

roasting onions in a pan topped with butter and rosemary sprigs

Here’s how this is going to go down, my friends: whole roasted onions, roasted with olive oil and butter, roasted with rosemary, roasted whole, roasted to sweet submission.

It’s cold. I mean… really cold. Here’s our chance to crank up the oven, throw these onions inside and lean against the oven door as they transform from sharp and bitey to soft and sweet! And while we’re at it, here’s how to roast any vegetable.

Oh, wait… you might be one of those people who think they don’t like onions. I’m here to tell you that you’re wrong. You exclusively like whole roasted onions, especially these.

And, if you’re feeling fancy, you might want to try this recipe for Ottolenghi’s Miso Butter Roasted Onions and Garlic! It’s like a savory onion candy.

10/10 recommend!

What are roasted onions?

This recipe is just like it sounds. You season and bake whole onions with slices of real butter on top. Roasting them softens the onions and brings out their natural sweetness.

If you aren’t a fan of the sharp flavor of onions, roasting them cuts the boldness back and makes them easier on your palette. And the butter, well… what doesn’t butter do?

Best types of onions to bake

When it comes to roasting or baking onions, use:

  • White onions
  • Yellow onions

They hold their shape and texture the best. Plus, both types have a strong flavor that sweetens magnificently when you bake them.

The best tips for making oven-roasted onions

The best thing about cooking is how much control you have over the way your food turns out! If you change my recipe, let me know. I’d love to hear what you did (and who knows… maybe I’ll try it that way?).

  • Quarter or slice the onions first. The smaller the onions are, the quicker they will bake, so keep an eye on the oven. It will also allow the butter and seasonings to go deep into the onion and become even MORE flavorful.
  • Fresh rosemary is the best herb to roast with onions, but try it with fresh sprigs of thyme. Its sweet earthiness can really bring out the buttery notes in the onions.
  • Drizzle balsamic vinegar on top of the onions right before you bake them. As the onions caramelize, the vinegar will break the onions down even more and release more sugar (what more could you want?), giving you tangy-sweet onions in the end.

whole roasted onions in a baking dish

How to roast an onion in the air fryer

Roasting is magic. It’s as simple as that, but you don’t have to heat up the entire kitchen just to roast a few onions (I’m looking at you, summertime humidity).

To roast onions in the air fryer, follow the same instructions in the recipe card!

Place the onions in the air fryer basket. Set it to 375°F and air fry them for 20 minutes. If they aren’t done to your liking, roast for another 10 minutes.

Serve and enjoy

These roasted onions – tops removed and toasted in their jackets – become soft, smooth, sweet, and almost spreadable.

The best way to eat a roasted onion is to slice it and eat it as a side dish along with a juicy pork chop and some fluffy mashed potatoes. Or, you could roast the onions and add a few slices on top of some baked sweet potatoes or on top of your favorite salad for a healthier option – if you’re a fan of that kind of thing.

How to store leftovers

Honestly, whole roasted onions taste the best when they are fresh out of the oven. You can store leftovers in an airtight container in the refrigerator for up to three days.

Just know that they will become softer, and their flavor will change. It just isn’t the same. Eat them fresh, trust me!

I hope you enjoy this recipe. Leave me a comment down below on how you plan to serve these roasted onions. I wanna know!

You might also enjoy these Miso Butter Roasted Onions!

Print
clock clock iconcutlery cutlery iconflag flag iconfolder folder iconinstagram instagram iconpinterest pinterest iconfacebook facebook iconprint print iconsquares squares iconheart heart iconheart solid heart solid icon

Whole Roasted Onions

★★★★★ 5 from 8 reviews
  • Author: Joy the Baker
  • Prep Time: 10
  • Cook Time: 45
  • Total Time: 55 minutes
Pin Recipe
Print Recipe

Ingredients

Scale
  • 9 small and medium yellow onions
  • 1/4 cup olive oil
  • 2 tablespoons unsalted butter, thinly sliced
  • coarse sea salt
  • fresh cracked black pepper
  • fresh rosemary sprigs

Instructions

  1. Place a rack in the upper third of the oven and preheat oven to 375 degrees F.
  2. Cut the tops off of each onion, but leave most of the skins on the onion.
  3. Arrange the onions in a square baking dish or a rimmed sheet pan.
  4. Drizzle the olive oil over the onions. Place a thin pat of butter on each onion.
  5. Sprinkle generously with salt and pepper and top with a rosemary sprig.
  6. Bake for 25 minutes until bubbling and tender.
  7. Increase the oven temperature to 400 degrees F and cook for another 15 to 20 minutes until the onions are completely tender and the tops are browned.
  8. Remove from the oven and allow to cool slightly.
  9. Remove the skins, slice and enjoy warm.

Did you make this recipe?

Share a photo and tag us — we can't wait to see what you've made!

Previous PostNext Post

Filed Under: Dinner, Healthy, Recipes, Savory

Previous Post: « Homemade Kitchen Hand Scrub and a little kitchen sparkle
Next Post: »

Reader Interactions

All Comments
I Made This
Questions
  1. Becky

    December 14, 2022 at 6:45 pm

    I have a question- do I have to leave the skins on? I’d. rather remove them first so when they come out of the oven I don’t have to mess around with them, I could just serve them up

    Reply
    • Rosy Yates

      March 9, 2023 at 11:31 am

      I just made them without skins and they were lovely , used thyme instead of rosemary as was using that for another accompanied dish

      Reply
  2. Chris

    May 29, 2022 at 9:29 pm

    Cooking these right now. For those with alternative ideas, maybe they could post their own recipes. This one is fine the way it is.

    Reply
    • mike

      June 25, 2022 at 8:33 pm

      When I try this recipe I might add a little Cajun seasoning.AlsoI thinking about using one of these onions with a baked Potato. Yum?

      Reply
  3. Josh

    April 3, 2022 at 8:40 pm

    I made this tonight with both yellow and red onions. I forgot to put my rosemary sprig on. I still really enjoyed it! Thanks!

    ★★★★★

    Reply
    • Josh Crocker

      May 8, 2022 at 4:47 pm

      I’m making these again tonight!

      Reply
  4. Sally

    February 19, 2022 at 4:44 pm

    I am an avid cook now in my mid 70s and have never ever posted a review before. BUT the results of this method of serving onions is mind boggling!!!!

    ★★★★★

    Reply
  5. Lindsey

    February 19, 2022 at 8:14 am

    Made this last night for dinner. Holy moly! Not only was the result absolutely incredible, but what a fantastic and extremely easy way to use up a large amount of onions before they go bad. I think this would be a great recipe to make on a Sunday and use for the rest of the week in other recipes. The next time I make it, I might try adding a little balsamic to the tops as well for added sweetness. I’m just so thrilled I found this recipe!

    ★★★★★

    Reply
  6. Rachel

    July 31, 2021 at 11:16 am

    I loved this recipe. Roasted them tonight for just a little over the suggested baking time and they turned out absolutely delicious.
    Such an easy and effective way to cook onions.
    This recipe is going to become a regular whenever I cook a roast.
    Thank you so much :-)

    ★★★★★

    Reply
  7. Long

    January 6, 2021 at 9:03 pm

    Great post! It is easy and detailed to follow. Thanks!

    Reply
  8. Earl

    December 2, 2020 at 1:53 pm

    Drop the Oil and Salt and lovely snack

    Reply
  9. Jason

    November 30, 2020 at 2:10 am

    Great suggestions for use. Thanks!

    ★★★★★

    Reply
  10. Kellie @Supperthymee

    November 12, 2020 at 9:27 am

    This is fabulous….but that pan looks like a nightmare to clean…I think I’ll slip some parchment underneath when I try this…

    Reply
  11. Anna

    March 19, 2019 at 9:07 am

    This recipe looks amazing! I’m so excited to try it.What would be something good to serve with this?

    ★★★★★

    Reply
    • Wesberry S

      June 7, 2021 at 6:43 am

      Someone suggested thinly sliced pork chops with the silky onions. Butter and EVOO oh my!

      ★★★★★

      Reply
  12. Leigh

    November 17, 2017 at 11:13 am

    A question, please – do you leave the root end intact or cut that off when you cut off the tops ?

    Reply
    • joythebaker

      November 18, 2017 at 10:50 pm

      I leave the root end intact and remove the root end and skin after baking.

      Reply
  13. kitlaughlin

    March 10, 2017 at 12:54 am

    The best part about this recipe (and doing it while I write) is *no peeling of the onions*. Gold, right there, let alone all the rest of the goodness!

    Reply
  14. Lynn Rohrs

    January 26, 2017 at 3:12 pm

    These were very good but took a LOT longer to cook than the recipe called for. I used the smallest onions I had but they were still likely bigger. I’d say it took at least an hour and 15 minutes and could have used a bit more.

    Reply
    • Sherrie Wesberry

      June 7, 2021 at 6:46 am

      Yes, the longer bake time sounds much better. Thought of that when reading it over. Melted onions. Yum.

      ★★★★★

      Reply
« Older Comments

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

Recipe rating ★☆ ★☆ ★☆ ★☆ ★☆

This site uses Akismet to reduce spam. Learn how your comment data is processed.

RELATED POSTS IN Dinner

French onion chicken in a bowl surrounded by glasses on a table
One-Pot French Onion Chicken Dinner

All the comforts of French onion soup turned into a cozy one-pot dinner.  This French Onion Chicken dinner is downright romantic and perfect for this winter weekend spent all cuddled up. You know every year I trapse in here with a version of Marry Me Chicken that is rumored to be soo good as to…

Read More

Guest: Julia Turshen’s Chicken Francese

Welcome our first December guest – Julia Turshen! Julia Turshen is a best selling cookbook author, food writer, chef, and food equity advocate. She lectures on food and home cooking and has published four solo books on the subject and has contributed to many others in collaboration or as a writer. She hosts the podcast…

Read More

Texture of homemade hamburger helper in pot.
One-Pot Homemade Hamburger Helper with Sneaky Veggies

You’ll be making this homemade hamburger helper recipe for dinner at least once a month. It’s a hearty and comforting dish and jam packed with secret veggies. Not that we need to keep veggies a secret but… sometimes we do. Let’s make classic Helper from scratch! Your kids (or the child inside your heart) will…

Read More

Primary Sidebar

Fresh baked emails, delivered to your inbox

Jump to Recipe

Receive recipes from Joy the Baker and updates on events at The Bakehouse.

HI! I’M JOY!

Jump to Recipe

Welcome! This has been my little corner of the internet since 2008!

I’m a baker, photographer, cookbook author and teacher.  I live laugh love in New Orleans. 

MORE ABOUT JOY AND THE TEAM

BOOKS + Magazines

Jump to Recipe

JOY THE BAKER 2022 SUMMER MAGAZINE

JOY THE BAKER 2021 HOLIDAY MAGAZINE

JOY THE BAKER 2020 HOLIDAY MAGAZINE

HOMEMADE DECADENCE

OVER EASY: SWEET AND SAVORY RECIPES FOR LEISURELY DAYS COOKBOOK

JOY THE BAKER COOKBOOK

Jump to Recipe
joy the baker on facebook joy the baker on twitter pinterest-social instagram-socialbloglovin-social

JOY @ WILLIAMS SONOMA

Jump to Recipe

SHOP THE CAKE LINE OF CAKE MIXES!

DRAKE ON CAKE

Jump to Recipe

Passionate from miles away since 2015.

Check it out on Instagram

Drake on cake instagram.

 

BREADS YOU’LL LOVE

jambalaya buttermilk biscuits in a row

Smoked Sausage Jambalaya Buttermilk Biscuits

inside of warm cinnamon roll on plate

How To Make The Best Single Serve Cinnamon Roll

Orange roll on a plate with a fork.

Christmas Morning Orange Rolls

LET’S MAKE COOKIES!

a stack of white chocolate macadamia nut cookies with a bite taken out of the top one with milk

Classic White Chocolate Macadamia Nut Cookies

wider shot of lemon bars stacked on a plate with a bite taken out of one lemon bar

My Favorite Classic Lemon Bars Recipe

completed recipe close up shot of a blondie so the toasted almonds, chocolate chips, and sea salt can be seen

My Best Classic Blondie Recipe

Footer

Instagram

joythebaker

📚Baker and author of books and magazines
🎂Creator @drakeoncake
💁🏻‍♀️Classes with me @thebakehousenola
🍰 Products with @williamssonoma

joythebaker
🍓🌼 Pan Dulce is the best way to bake spring! 🍓🌼 Pan Dulce is the best way to bake spring! Full recipe linked in the @joythebaker bio! Xo
Second coffee: the perfect way to re-start the day Second coffee: the perfect way to re-start the day. 
✨Beignet Café au Lait✨⁣
⁣1/3 cup sweetened condensed milk⁣⁣
Splash of vanilla extract⁣⁣
½ cup heavy cream, whipped to stiff peaks⁣⁣
2 cups fresh brewed strong coffee⁣⁣
½ cup toasted cinnamon cereal, lightly crushed⁣⁣
Powdered sugar for topping⁣⁣
⁣⁣
Place sweetened condensed milk and vanilla in a small bowl. Add half of the whipped cream and fold to combine.  Add the remaining half and fold until you have a fluffy sweet cream. ⁣⁣
⁣⁣
Divide brewed coffee between two mugs. Spoon dream on top.  Sprinkle cinnamon cereal between the cups.  Dust with powdered sugar and enjoy immediately.
Life Skill No. 458: How to Make 1️⃣2️⃣ Cup Life Skill No. 458: How to Make 1️⃣2️⃣ Cupcakes with just 1️⃣ Stick of Butter⁣
⁣
Full recipe linked in my bio! xo
Someone call @foodnetwork because Dad and I need a Someone call @foodnetwork because Dad and I need a baking show stat. Here’s our very best chocolate chip cookies and all the little tips that make them perfection. ✨🍪 Find the full recipe linked in the profile!
We’re baking the classics on Joy the Baker this We’re baking the classics on Joy the Baker this month and up next, my very favorite Lemon Bar recipe with fresh lemon juice and the tiniest hint of coriander. ⁣🍋🌼✨
⁣
Find the full recipe linked in the profile and bust out the white chocolate and macadamia nuts for next week’s bake! ⁣
⁣
#lemonbars #easybaking #bakedfromscratch #joythebaker
Day in the Life: out in the woods writing a little Day in the Life: out in the woods writing a little cookbook about camp food. 💖🏕️🙋🏻‍♀️
Load More... Follow on Instagram

Copyright © 2023 · Joy the Baker
All rights reserved. Violators will be whupped and sent to bed with no dessert · Privacy Policy

Scroll Up