Preheat the oven to 375℉. Spray a 9×9 or 8×8-inch baking dish with cooking spray.
In a bowl, combine all of the ingredients and mix.
Transfer to the prepared dish. Top with a few additional frozen berries and sliced almonds, if desired.
Bake for 30-35 minutes or until center is set.
Let sit for 10 minutes before serving.
Top with whipped topping or yogurt and maple syrup if desired.
