Preheat oven to 350°F (175°C). Line a muffin tin with paper liners or grease lightly.
In a large bowl, combine cottage cheese, pumpkin puree, honey, and eggs. Mix until smooth.
Stir in rolled oats, protein powder, baking powder, cinnamon, nutmeg, and salt until well combined. Add walnuts if using.
Spoon the batter into the prepared muffin tin, filling each cup about ¾ full. Bake for 18-20 minutes or until a toothpick comes out clean.
