Preheat the oven to 375°F. Butter the inside of a 9x13 baking dish. In a bowl, whisk together the oats, walnuts, baking powder, cinnamon, and salt. Set aside. In another bowl, whisk together the almond milk, maple syrup, egg, and vanilla. Set aside. Arrange the bananas in a single layer in the bottom of the prepared baking dish. Sprinkle two-thirds of the blueberries in the spaces in-between bananas. Cover fruit with the oatmeal mixture. Slowly drizzle the almond milk mixture over the oats. Place the remaining berries, coconut, and orange zest across the top. Bake for 25 to 30 minutes, until the top is golden-brown colored, and the oat mixture has set. Remove from the oven and let cool for a few minutes. When it comes to serving, I like to serve it with a chilled glass of Almond Breeze Unsweetened Vanilla Almond Milk.