Preheat your waffle iron to a medium-high setting.
In a high-speed blender, combine the egg whites, cottage cheese, oat flour, baking powder, vanilla extract, and cinnamon.
Blend on high for 30-45 seconds until the batter is completely smooth and aerated.
While the iron heats, place the mixed berries, lemon juice, and maple syrup in a small saucepan over medium heat.
Simmer the berry mixture for 5-7 minutes, stirring occasionally and lightly mashing the berries until the sauce has thickened into a compote.
Lightly brush the waffle iron plates with avocado oil to prevent sticking.
Pour the batter into the waffle iron and cook for 4-6 minutes, or until the waffles are golden brown and firm to the touch.
Carefully remove the waffles and serve immediately topped with the warm berry compote.