Pre heat oven to 350F.
Make the crumble first. It's imperative that the crumble be chilled in the refrigerator before baking because we're using vegan butter which melts much quicker than regular butter so don't skip this step! Combine all the crumble ingredients in a bowl using a fork to make large crumble pieces. If your flour is dry you may need extra maple syrup. Refrigerate at least 10-15 minutes before baking
If you're making the extra blueberry layer you can make it now by combining the ingredients in a saucepan and simmering for 5 minutes until thickened
In the 8x8 pan mix the baked oat layer by combining and stirring the oats, baking powder, cinnamon, salt, eggs, milk, maple syrup, vanilla, oil, protein powder and blueberries
If using the extra blueberry layer spread it over the top of the oats and swirl into the oats
Crumble the topping over the oats
Bake for 40-50 minutes on the top shelf uncovered. If you're crumble starts to get too brown cover with tin foil. Using a toothpick check the center to ensure it's fully cooked. If not check in 5 minute intervals until completed(In my oven in Florida -high humidity- an in a glass baking dish, uncovered it took the oats exactly 50 minutes to bake completely