1 cup (2 sticks) unsalted butter, room temperature, plus more for pans
1 3/4 cups sugar, plus more for sprinkling fruit
4 large eggs
2 teaspoons pure vanilla extract
1 1/4 cups milk
10 ounces strawberries, hulled and cut into small dice, plus more for garnish
Preheat oven to 350 degrees. Line 2 1/2 standard 12-cup cupcake pans with paper liners; set aside.
Into a medium bowl, sift together flours, baking powder, and salt; set aside.
In the bowl of an electric mixer fitted with the paddle attachment, beat the butter and sugar until light and fluffy, 3 to 4 minutes, scraping down the sides of the bowl as needed. Beat in eggs, one at a time, and then beat in vanilla. With the mixer on low speed, add the flour mixture in three parts, alternating with the milk and beginning and ending with the flour; beat until combined after each addition. Fold in strawberries.
Divide the batter evenly among the prepared cups so that each is about two-thirds full, about 2 ounces each. Bake, rotating the pans halfway through, until the cupcakes are golden brown and a cake tester inserted in the centers comes out clean, about 20 minutes. Transfer pans to a wire rack to cool for 5 minutes. Remove cupcakes from pan and cool completely on wire racks.
1 1/2 cups (12 ounces) strawberry jam, pureed in a food processor
In the heatproof bowl of an electric mixer set over a saucepan of simmering water, combine egg whites and sugar. Cook, whisking constantly, until sugar has dissolved and mixture is warm to the touch (about 160 degrees).
Attach the bowl to the mixer fitted with the whisk attachment. Beat the egg-white mixture on high speed until it holds stiff (but not dry) peaks. Continue beating until the mixture is fluffy and cooled, about 6 minutes.
Switch to the paddle attachment. With mixer on medium-low speed, add butter several tablespoons at a time, beating well after each addition. (If frosting appears to separate after all the butter has been added, beat on medium-high speed until smooth again, 3 to 5 minutes more.) Beat in vanilla. Beat on lowest speed to eliminate any air bubbles, about 2 minutes. Stir in strawberry jam with a rubber spatula until frosting is smooth.
They were a light, fresh tasting cupcake… definitely went on our “make again” list.