(for the cupcakes)
- 1 stick unsalted butter, room temperature
- 1 3/4 cups all-purpose flour
- 2 teaspoons baking powder
- 1/2 teaspoon salt
- 3/4 cup sugar
- 2 large eggs, room temperature
- 1 teaspoon pure vanilla extract
- 1/2 cup whole milk
(for the strawberry swiss meringue buttercream frosting)
- 4 large egg whites
- 1 1/4 cups sugar
- 1 cup unsalted butter(2 sticks)
- 1/3 cup strawberry jam
- Preheat oven to 350 degrees. Grease a standard 12-cup muffin pan, or use paper liners.
- In a medium bowl, whisk together flour, baking powder, and salt; set aside.
- With an electric mixer, beat butter and sugar until light and fluffy. Add eggs one at a time, beating well after each addition; add vanilla, and mix until combined.
- On low speed, beat in half the flour mixture, followed by milk; end with remaining flour mixture. Mix just until incorporated (do not overmix).
- Fill muffin cups with 3 tablespoons of each batter, side by side.. Bake until a toothpick inserted in center of a cupcake comes out clean, 18 to 20 minutes. Cool cupcakes in pan, 5 minutes; transfer to a wire rack to cool completely.
- Put egg whites and sugar into the top of a double boiler over a pan of simmering water. Whisking constantly, cook until sugar has dissolved and mixture is warm (about 160 degrees).
- Pour heated egg whites into the bowl of an electric mixer fitted with the whisk attachment. Beat egg white mixture on high speed until it forms stiff (but not dry) peaks. Continue beating until fluffy and cooled, about 7 minutes.
- Switch to the paddle attachment. With mixer on medium-low, add butter two tablespoons at a time, beating well after each addition. Increase speed to medium-high; continue beating until frosting appears thick, about 3 minutes.
- Reduce speed to low; add strawberry jam and continue beating 2 minutes to eliminate air bubbles.