Preheat oven to 350°F (175°C). Grease and flour two 9-inch round cake pans. In a medium bowl, whisk together flour, baking powder, baking soda, and salt. In a large mixing bowl, cream softened butter and sugar until light and fluffy (3-4 minutes). Add eggs one at a time, beating well after each addition. Mix in vanilla extract.

Gradually add the dry ingredients to the butter mixture, alternating with buttermilk, beginning and ending with dry ingredients. Fold in strawberry puree until just combined. Divide batter evenly between prepared pans and smooth the tops.

Bake for 25-30 minutes until toothpick comes out clean. Let cakes cool in pans for 10 minutes before transferring to wire rack to cool completely.

Prepare crunchy topping by combining crushed shortbread cookies, freeze-dried strawberries, melted butter, and sugar in small bowl. Mix until well combined and set aside.

Prepare frosting by beating softened butter until creamy. Gradually add powdered sugar, beating on low speed until combined. Beat on high for 3 minutes. Add strawberry puree, vanilla extract, and salt. Beat until smooth and fluffy. Add heavy cream as needed for consistency.

Place one cake layer on serving plate. Spread generous layer of frosting over top. Place second layer on top and frost entire cake. Generously press crunchy topping onto sides and top. Refrigerate for 30 minutes to set frosting.