For the Cake:
- 1 (15.25 ounce) box white cake mix
- 8 ounces sour cream, divided
- 1/4 cup water
- 1/4 cup vegetable oil
- 3 large eggs
- 1 cup cream of coconut like Coco Lopez (buy a 15 ounce can)
For the Sour Cream Layer:
- Remaining 4 ounces sour cream
- 3 tablespoons cream of coconut
- 2 tablespoons powdered sugar
For the Frosting:
- 2 8-ounce blocks cream cheese
- 1/2 cup unsalted butter, at room temperature
- 1 pound powdered sugar
- 1 teaspoon pure vanilla extract
- Splash of milk
- 2–3 cups sweetened shredded coconut
- Place a rack in the upper third of the oven and preheat oven to 350 degrees F. Grease a 9×13-inch baking pan with nonstick cooking spray and set aside.
- In a large bowl with a set of electric hand beaters, combine dry cake mix, half of the sour cream container (4 ounces), and the rest of the cake ingredients. Beat on high for three to five minutes until well combined.
- Pour the batter into the prepared pan and bake for 26-30 minutes or until a toothpick inserted in the center comes out dry with a few moist crumbs, not wet batter.
- While the cake bakes, in a small bowl combine remaining sour cream, cream of coconut and powdered sugar. Whisk until no lumps remain and set aside.
- Remove the baked cake from the oven and allow to cool for five minutes. Use a toothpick to prick holes across the top of the cake and spread the sour cream frosting across the warm cake. Cover loosely and allow the cake to cool to room temperature.
- While the cake cools, make the cream cheese frosting. In a medium bowl using electric hand beaters, beat cream cheese around the bowl to soften. Add the softened butter and beat to combine. Add the powdered sugar and vanilla and a small splash of milk. Beat until thick and smooth, about 3 minutes.
- Toast 1 cup of shredded coconut on a small sheet pan in the oven until golden brown, abbot 5 minutes but keep a close eye on it. Toss with untoasted coconut.
- Place 1/3 of the cream cheese frosting in a piping bag fitted with a star tip. Frost the cooled cake with room temperature cream cheese frosting from edge to edge.