Preheat the oven to 350°F (177°C).
Line an 8-inch square baking pan with parchment paper, leaving some overhang on the sides for easy removal later.
Add pumpkin, peanut butter, cocoa powder and maple syrup to a food processor. Blend until you have a smooth batter, scraping down the sides of the food processor with a spatula as needed. Your mixture will be very thick, almost like a paste.
Transfer the batter to the prepared baking pan, spreading it evenly with a spatula.
Bake for about 25-35 minutes (mine were done at 30 minutes) or until the surface looks cooked and slightly cracked. The brownies should have puffed up slightly as well but they won't rise that much. Let the brownies fully cool in the pan before cutting and serving.
Cut brownies with a sharp knife. I recommend wiping the blade between each cut because the brownies are very fudgy. Store uneaten brownies in an airtight container in the fridge.
