Blend the cottage cheese in a food processor until completely smooth, about 30 seconds. Set aside.

In a large bowl, whisk together the flour, baking powder, baking soda, salt, and pumpkin pie spice.

In a separate bowl, whisk the pumpkin puree, brown sugar, oil, eggs, and vanilla until smooth. Stir in the blended cottage cheese.

Pour the wet ingredients into the dry ingredients and fold gently with a spatula just until no dry flour pockets remain.

Preheat oven to 375°F (190°C). Line a 12-cup muffin tin with paper liners. Divide batter evenly among the cups, filling each about three-quarters full. Bake 18 to 22 minutes, until a toothpick inserted in the center comes out clean. Cool in the tin for 5 minutes, then transfer to a wire rack. Serve warm or at room temperature.