Set oven to 400F.
In a bowl, mix together the dry ingredients. Set aside.
In another bowl, whisk together the wet ingredients.
Spray a baking dish or cast iron skillet with baking spray. Add about half of the berries to the skillet. Scatter them around the baking dish or skillet.
Pour the dry mixture over the berries and use a spatula to ensure the dry mixture is spread evenly throughout the pan.
Pour the wet ingredients over the dry ingredients and tap the baking dish or skillet to ensure the wet ingredients completely cover the dry ingredients. Use a spatula to lightly pat down areas where the dry ingredients are not covered by the wet ingredients. Then add the rest of the frozen berries on top.
Place in the oven and bake for 30 minutes or until you can pierce it with a toothpick and it comes out clean (minus the berries), and the edges and top of the bake are golden brown.
Allow it to cool before slicing. Garnish and enjoy with a moderate serving of Greek yogurt or your favorite lean protein shake.