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

In a mixing bowl, whisk together cake flour, baking powder, baking soda, and salt. Set aside.

Beat softened butter and granulated sugar together until light and fluffy. Add egg whites and vanilla extract, mixing until smooth.

Gently alternate adding dry ingredients and buttermilk to the butter mixture, mixing until just combined.

Preheat the oven to 350°F (175°C). Line the cupcake tin and fill each liner 2/3 full with batter. Bake for 16-18 minutes.

To make the frosting, beat softened butter until fluffy, add cream cheese, then mix in powdered sugar and freeze-dried strawberries.

Once cooled, hollow out the centers of the cupcakes, fill with strawberry jam, and top generously with frosting.