Preheat oven to 350 ℉. Grease and flour an 8-inch round cake pan. In a small bowl combine sliced strawberries and 1 tablespoon of the sugar. Stir and set aside for 15 minutes. Meanwhile blend the freeze-dried strawberries into a fine powder. Pour the powder into a small dish and set aside. Blend the freeze-dried strawberries from the frosting ingredients as well and set aside in a small bowl.
In a medium bowl, combine the flour, baking powder, baking soda, and salt. Set aside.
Add the macerated strawberries to the blender, reserving the juice for later. Blend for about 1 minute or until no large chunks of strawberry remain. Set aside. In a large bowl cream together the butter, remaining sugar and strawberry powder. Add the vanilla, eggs, sour cream, and blended strawberries. Beat just until combined.
Add half the flour mixture and half of the buttermilk. Beat just until combined. Add the remaining flour mixture and buttermilk and beat once more just until combined. Pour the batter into prepared cake pan and bake for 25-30 minutes or until a toothpick inserted in the center comes out clean.
Let the cake cool on a wire rack. Once mostly cooled off, carefully invert the cake onto a cooling rack and let cool completely. Once cooled, use a pastry brush to apply the juice from the macerated strawberries to the top of the cake.
To make the frosting, beat together the cream cheese, butter, and vanilla until light and fluffy. Add the strawberry powder and powdered sugar and beat until well combined. Scoop the frosting out into the center of the cake and spread out using a spoon or offset spatula. Decorate with whole strawberries if desired.
Store cake in an airtight container at room temperature or in the refrigerator for up to 5 days. Cake is best served within 2 days.