Set aside 12 strawberries with hulls for cake garnish; remove hulls from remaining strawberries. Mash 2 cups of hulled strawberries with a potato masher.
Process remaining hulled berries and next 3 ingredients in a food processor until smooth. Pour over mashed berries; stir gently. Cover and chill up to 8 hours.
Note: Cake can be made up to 1 day in advance and refrigerated. Let stand at room temperature at least 2 hours before serving.