Start by preheating your oven to 350°F (177°C) and lining a 12-cup muffin pan with cupcake liners. You'll bake a second batch for the remaining cupcakes.

Puree 5 strawberries until chunky to get about 1/3 cup, then finely chop the rest. Set both aside.

Beat the egg whites to soft peaks using a mixer with a whisk attachment, then set aside.

Sift together flour, cornstarch, baking powder, and salt. In another bowl, cream the butter and sugar, then add the egg yolk and vanilla. Alternate adding dry ingredients and milk to this mixture, then fold in the egg whites, strawberry puree, and chopped strawberries.

Fill cupcake liners halfway with batter and bake for 20-24 minutes. Let cool in the pan for 5 minutes, then transfer to a rack to cool completely.

For the frosting, process freeze-dried strawberries into a powder. Beat butter until creamy, then gradually add confectioners’ sugar, strawberry powder, cream, and vanilla extract. Adjust thickness and sweetness as needed, then frost the cooled cupcakes.