In a medium saucepan, combine quartered fresh strawberries, granulated sugar, and lemon juice. Cook over medium heat for 15–17 minutes, stirring occasionally, until thickened.

Remove from heat and let the jam cool completely before filling the cupcakes.

In a bowl, sift together the cake flour, baking powder, baking soda, and salt.

Beat softened butter and granulated sugar for 2-3 minutes until light and fluffy.

Add egg whites and vanilla extract, mixing until smooth.

Alternately add the dry flour mixture and buttermilk to the batter, mixing until just combined.

Preheat oven to 350°F (175°C). Fill cupcake liners two-thirds full, and bake for 16-18 minutes.

Cool in the pan for 10 minutes, then transfer to a wire rack.

Beat cold cream cheese until fluffy, add powdered sugar, and then incorporate ground freeze-dried strawberries.

Create a well in each cooled cupcake, fill with strawberry jam, and pipe frosting on top.