Preheat oven to 350° F. Prepare an 8" by 8" baking dish by lightly coating it with nonstick coconut oil spray.
In a medium bowl, mix together all of the casserole ingredients. Spread into the prepared baking dish.
In a small bowl, mix together all of the crumble ingredients. Sprinkle over the top of the casserole. Sprinkle with chopped pecans if you desire (this makes the dish a Crossover on Trim Healthy Mama).