Homemade Funfetti Cake has never been easier. One pan and one layer of frosting is all you need for an unforgettably festive and delicious birthday cake!
Preheat the oven to 350°F and have ready a greased 9x13" baking dish, preferably metal or glass.
Sift the cake flour, baking powder, baking soda, and salt over a medium-sized mixing bowl. Set aside until ready to use.
Add the butter and sugar to a large bowl and using a handheld mixer, mix until fluffy and pale yellow in color (about 3-5 minutes). You could also use a stand mixer fitted with a paddle attachment for this task.
Add the oil and mix until well-blended. Add the eggs, one at a time, mixing well after each addition. Add the sour cream and the vanilla and mix again. Scrape down the sides and the bottom of the bowl using a silicone spatula and mix once more.
With the mixer on low, add the dry ingredients in 3 rounds, alternating with the buttermilk (adding it in 2 rounds). Scrape the sides and the bottom of the bowl, and mix once more.
Fold in 1/3 cup Jimmie sprinkles and transfer the batter to the prepared pan and smooth over the top. Bake for 28-32 minutes (checking at the 28-minute mark). Set the cake aside to cool completely on a wire rack before icing.
For the frosting, you will need a large mixing bowl and a handheld mixer or a stand mixer fitted with a paddle attachment. Add the butter to the bowl and mix on medium-high speed for 2-4 minutes, smooth and almost doubled in volume.
Add the powdered sugar, milk, vanilla, and salt and begin mixing on low. Once the sugar is mostly incorporated, you can begin mixing on medium-high. Mix for 2 minutes more, until light and fluffy. Add 1/4 cup of Jimmie sprinkles and mix on low until evenly distributed.
Spread the icing evenly over the top of the cake and finish it off with the remaining 1/4 cup of Jimmie sprinkles. Cut into 16 slices, serve, and enjoy!
The cake is ready when the center of it springs back ever so slightly after a gentle poke or a toothpick inserted in the center comes out with only a few crumbs clinging to it.
The Anthony Kitchen