Vanilla Confetti Cake with Chocolate-Cardamom Ganache
This cake is my go-to when I'm short on time but want to make something really crowd-pleasing. It's an easy homemade sheet cake with lots of flavor and a fun surprise from rainbow sprinkles mixed into the batter. It uses baking staples, and even takes advantage of a quick substitution for buttermilk by mixing cream and lemon juice. The addition of cardamom to the frosting is optional, but it adds a fresh touch to a traditional dessert.
Preheat the oven to 350 degrees F. Position a baking rack in the middle of the oven.
For the cake: Spray a 13-by-18-inch rimmed baking sheet with cooking spray. Stir the cream and lemon juice together in a liquid measuring cup and set aside to curdle for 5 to 7 minutes.
Whisk the flour, sugar, baking powder, baking soda and salt together in a large bowl. Whisk the melted butter, eggs and vanilla together in a medium bowl. Whisk in the cream and lemon juice mixture. Stir the wet ingredients into the dry ingredients. Gently fold in the sprinkles.
Pour the batter into the prepared baking sheet and spread evenly with a spatula. Bake on the middle rack of the oven until a toothpick inserted in the center comes out clean, 15 to 17 minutes. Cool the cake in the pan at least 30 minutes.
For the frosting: Combine the cream and cardamom if using in a small saucepan and bring to a simmer over medium-low heat, stirring occasionally, 2 to 3 minutes. Place the chopped chocolate in a heat-proof bowl. Slowly whisk the hot cream into the chocolate until smooth. Whisk in the room temperature butter, one tablespoon at a time, until melted and smooth. Whisk in the vanilla and salt.
Spread the frosting onto the cooled cake and decorate with sprinkles. Enjoy!
Be sure to use sprinkles (also called jimmies), not nonpareils, in this cake; nonpareils will bleed into the batter.