Preheat oven to 400°F (204°C). Line or grease a 12-cup muffin pan.
Add cottage cheese to a blender or food processor and blend until completely smooth.
In a large bowl, whisk together blended cottage cheese, milk, oil, (maple/honey), vanilla, lemon zest and cinnamon (if using), until well combined.
In a separate bowl, whisk together flour, baking powder, baking soda, and salt.
Gently fold the dry ingredients into the wet ingredients just until combined. Do not overmix.
Fold in blueberries. If using frozen blueberries, toss them with 1 teaspoon of flour before adding.
Let the batter rest for 5 minutes for taller muffin tops.
Divide batter evenly between muffin cups, filling nearly to the top.
Sprinkle tops with coarse sugar if using.
Bake at 400°F for 5 minutes, then reduce oven temperature to 350°F (177°C) and bake for 14–16 minutes, or until a toothpick inserted comes out clean.
Cool muffins in the pan for 10 minutes, then transfer to a wire rack.
