Follow the directions (including the preheating the oven) on the cake mix box
Combine heavy cream, powdered sugar, and vanilla and mix thoroghly until thick
Clean and slice all strawberries
After baking the cupcakes let them cool. Once cool slice cupcake in half put a layer of strawberries then a layer of whipped cream then put the top of cupcake on top cupcake with a dallop of whipped cream and top with a strawberry.