Ingredients
Scale
- FOR THE CAKE:
- 6 tablespoons unsalted butter (at room temperature)
- 1/4 cup plus 1 tablespoon granulated sugar
- 1 large egg
- 2 large egg yolks
- 2 teaspoons vanilla extract
- 3/4 teaspoon baking powder
- 1/4 teaspoon baking soda
- 1/2 teaspoon table or fine sea salt
- 3/4 cup buttermilk
- 2 tablespoons cornstarch
- 1 1/4 cups plus 2 tablespoons AP flour
- FOR THE FROSTING:
- 1/2 cup unsalted butter, at room temperature
- 1 1/2 cups powdered sugar
- Pinch of fine sea salt
- 2 ounces unsweetened chocolate, melted and cooled
- 1 tablespoon cream or whole milk
- 1/2 teaspoon vanilla extract
Instructions
- FOR THE CAKE:
- Heat the oven to 350°.
- Coat an 8" square cake pan with nonstick spray and line the bottom with parchment paper.
- Beat the butter and sugar together in a large bowl with an electric mixer until fluffy.
- Beat in egg, yolks, and vanilla until combined.
- Scrape down the bowl, and then sprinkle the baking powder, baking soda, and salt over the batter and beat until very well combined.
- Add the buttermilk and mix to combine (the batter may look curly).
- Add the cornstarch and flour and mix until the flour just disappears.
- Scrape the batter into the prepared pan and smooth the top.
- Bake for 25 to 27 minutes, until a toothpick inserted into the center of cake comes out batter-free.
- Let cool in the pan on a cooling rack for 10 minutes, then run a knife around the cake to ensure that it is loose.
- Flip in out onto a cooling rack, and then flip back right side up again onto another.
- Let cool completely before frosting.
- FOR THE FROSTING:
- Beat the butter, powdered sugar and salt in a large bowl with electric beaters (or paddle attachment for stand mixer) until fluffy.
- Pour in the chocolate, cream or milk, and vanilla and beat until combined, then 1 more minute to whip it further.
- Prep Time: 30 mins
- Cook Time: 25 mins
- Category: Dessert