Preheat oven to 375 degrees F.
Mix egg whites in a clean bowl until they are stiff and form peaks. Set aside.
Cream butter on medium speed until it's nearly white. Add in sugar, vanilla and milk. In a separate bowl, combine dry ingredients and whisk. Slowly add dry ingredients to wet ingredients, mixing as you go. Add in egg whites and mix gently.
Fill cupcake liners 2/3 of the way full. Bake at 375 F for 20 minutes, until tops of cupcakes are beginning to golden. Remove and let cool completely.
Sweet Cream: Combine and mix using a hand-held mixer (or Kitchenaid) until thickened. Store in the fridge until ready to use.
Top cupcakes with sweet cream and berries. Drizzle with melted chocolate just before serving.