Pumpkin-Chocolate Muffins

Preheat the oven to 375 degrees F (190 degrees C). Grease 18 standard-sized muffin cups, or line with paper liners.

Whisk together flour, white sugar, brown sugar, cocoa powder, cinnamon, baking soda, and salt in a large bowl. Whisk together pumpkin puree, oil, eggs, and vanilla extract in a second bowl until well combined. Pour pumpkin mixture into the flour mixture and stir until you see no more flour. Stir in walnuts and chocolate chips. Spoon batter into the prepared muffin cups, filling each 3/4 full, to create a nice, rounded top.

Bake in the preheated oven until a toothpick inserted into the center comes out clean, 30 to 35 minutes. Cool in the tins for 5 minutes. Remove from the tins and transfer to a wire rack to cool for another 10 minutes.

Dust muffins lightly with powdered sugar while they are still warm to the touch.