The Preparation
Make raspberry filling: cook raspberries and sugar in a small saucepan over medium heat. Stir in cornstarch dissolved in a little water. Cook until thickened. Cool completely.
Preheat oven to 350°F and line a muffin tin with cupcake liners.
Whisk flour, baking powder, and salt together.
Cream butter and sugar until light and fluffy. Beat in eggs one at a time, then vanilla.
Alternately add dry ingredients and combined sour cream/milk, beginning and ending with dry ingredients.
Fill liners 2/3 full and bake 18-20 minutes until a toothpick comes out clean.
Cool completely.
Use a small knife or cupcake corer to hollow out the center of each cupcake.
Fill each center with raspberry filling.
Make frosting: beat cream cheese and peanut butter until smooth. Add powdered sugar and vanilla, beating until fluffy. Add heavy cream to reach desired consistency.
Pipe or spread frosting over cupcakes. Garnish with a small dollop of raspberry jam on top.
