Place a steamer insert into a saucepan and fill with water to just below the bottom of the steamer. Bring water to a boil. Add cauliflower, cover, and steam until tender, about 10 minutes. Transfer cauliflower to a blender and blend until smooth. Measure 1 cup pureed cauliflower and store any remaining in a container in the refrigerator for another use.
Stir 1 cup cauliflower puree and cottage cheese together in a large bowl until smooth. Mix flour, brown sugar, baking powder, nutmeg, and cinnamon into cauliflower mixture until batter is just mixed and thickened. Add eggs to batter until thoroughly mixed. Stir milk into batter, adding 1 tablespoon more at a time if needed, until batter is smooth.
Heat butter in a large frying pan over medium heat; drop heaping tablespoons batter into the melted butter. Cook until batter begins to bubble, 3 to 4 minutes. Flip pancakes and cook other side until browned, 3 to 4 more minutes. The inside of these pancakes will be softer than traditional pancakes. Repeat with remaining batter.