Preheat oven to 350°F (175°C) and line muffin tin with cupcake liners
Whisk together flour, baking powder, and salt in medium bowl
Cream butter and sugar until light and fluffy (about 3 minutes)
Add eggs one at a time, then vanilla, buttermilk and strawberry puree
Gradually mix in dry ingredients until just combined
Divide batter evenly among 12 cupcake liners (about ¾ full)
Bake 18-20 minutes until toothpick comes out clean
Cool completely on wire rack
Make topping: Combine crushed Oreos, freeze-dried strawberries and melted butter
Make frosting: Beat butter until creamy, gradually add powdered sugar, then strawberry puree and vanilla
Frost cooled cupcakes and dip tops in crumb mixture