01 - Preheat oven to 350°F. Generously grease a 9x9-inch baking dish with butter.
02 - In a large bowl, whisk cottage cheese, eggs, milk, maple syrup, vanilla, and melted butter until completely smooth and incorporated.
03 - In a separate bowl, mix rolled oats, baking powder, cinnamon, and salt until evenly distributed.
04 - Pour dry ingredients into wet mixture and stir until just combined, being careful not to overmix.
05 - Gently fold blueberries into the batter, taking care not to crush them.
06 - Pour mixture into prepared baking dish. Smooth the top evenly with a spatula.
07 - Sprinkle almonds or walnuts and coarse or brown sugar evenly over the top, if using.
08 - Bake for 35-40 minutes until center is set and top is golden brown.
09 - Let cool for 10 minutes before slicing. Serve warm or at room temperature.