01 - Set oven to 350°F (175°C). Lightly grease a 9x13-inch baking dish.
02 - Evenly distribute bread cubes in the greased baking dish. Scatter blueberries across the bread.
03 - In a blender, combine milk, cottage cheese or Greek yogurt, eggs, protein powder, maple syrup, vanilla extract, cinnamon, and salt. Blend until fully smooth.
04 - Pour the blended mixture over bread and blueberries, pressing gently to help the bread absorb liquid.
05 - Sprinkle with chopped pecans or walnuts and sugar if using.
06 - Cover baking dish with foil and bake for 30 minutes.
07 - Remove foil and bake an additional 10 minutes, until bake is well-puffed and golden.
08 - Allow to cool slightly before serving. Enjoy warm, with extra maple syrup if desired.