Directions

1. Preheat the oven to 350°F. Grease three 8-inch round cake pans and line the bottoms with parchment paper.

2. In a medium bowl, sift together the cake flour, all-purpose flour, baking powder, and baking soda, then lightly stir in the salt and set aside. In a medium bowl or large measuring cup, whisk together the sour cream, heavy cream, and vanilla and almond extracts and set aside.

3. In a stand mixer fitted with a paddle, combine the butter, coconut oil, and sugar and beat on medium high until pale and fluffy, 3 to 4 minutes. Add the egg whites one at a time, mixing well after each addition and scraping down the sides of the bowl with a rubber spatula as needed to ensure that everything combines evenly. Reduce the speed to low and add the flour mixture and cream mixture in three alternating additions, mixing until mostly combined. Turn off the mixer, add the sprinkles, and use your spatula to finish up the mixing by hand, making sure to combine thoroughly without overmixing.

4. Divide the batter evenly among the prepared pans, spreading the batter out evenly with the back of a spoon or an offset spatula. Bake until the tops are springy and a toothpick inserted into the centers comes out clean or with just a few crumbs on it; begin checking for doneness at 28 minutes. If they’re not yet done, check frequently until they are because you want to avoid overbaking at all costs. Let cool in the pans for 10 minutes, then transfer to a wire rack to cool completely.

5. To make the frosting, in a stand mixer fitted with a paddle, combine the butter, powdered sugar, and salt and mix on low until you’re confident that sugar won’t fly everywhere, then gradually increase the speed to medium high and continue to mix until smooth and fluffy, about 2 minutes. Lower the speed to medium, add the vanilla and almond extracts and cream cheese, and mix until just combined, then mix in the rainbow chips. Scrape down the sides of the bowl with a rubber spatula as needed to ensure that everything combines evenly.

6. To assemble, level the cake layers and stack them up with a layer of frosting in between them. Frost the cake all over.

7. Note: You can also make this into 32 cupcakes or a 9 × 13-inch cake. To bake, begin checking for doneness at 18 minutes for cupcakes and 50 minutes for a 9 x 13-inch cake. The frosting amount will yield enough for a 9 x 13-inch cake and just enough for a thin layer on each cupcake. (If you’re a big frosting person, make an additional half batch of frosting.)

Rainbow Chips

1. Line a sheet pan (or quarter sheet pan, if that fits better in your fridge or freezer) with parchment paper.

2. Melt the chocolate in a double boiler or in a bowl in the microwave in 30-second increments, stirring after each, until smooth. Divide into as many bowls as you want colors (I’d recommend 4 or 5) and stir food coloring into each. (White chocolate is a little finicky; if you find it seizes up when you add the food coloring, stir in melted coconut oil a little at a time until it smooths out again.)

3. Spread on the parchment in blobs and place in the fridge or freezer until firm, about 10 minutes. Chop into little bits.

4. Store in an airtight container at room temperature for up to several weeks.

5. Note: This recipe makes twice what you need for this cake. It’s fun to have leftovers for decor or other uses, but if you’d like to avoid leftovers, then simply make a half batch.