Created by KarenSTL on February 18, 2018
Step 1: Preheat oven to 350*.
Step 2: To make batter, first process oats in a food processor until finely ground.
Step 3: Lightly spoon flour into a dry measuring cup; level with a knife. (too much flour will make this cake dry). Add flour, sugar, baking powder and salt to food processor; blend well.
Step 4: Add butter; pulse 5 times or until combined. Spoon mixture into a large bowl.
Step 5: Combine milk, eggs, and vanilla in a small bowl, stirring just until blended. Add to oat mixture, stirring to combine. Gently stir in frozen blackberries (do not use fresh or thawed blackberries as they will bake away and the juices will discolor the batter).
Step 6: Pour mixture into a 9-inch pie plate or 8x8 inch glass baking dish, coated with cooking spray.
Step 7: Combine all topping ingredients in a food processor and process until finely chopped. Sprinkle topping evenly over batter.
Step 8: Bake for 45 mins or until lightly browned.
Step 9: Cool completely on a wire rack.