Preheat oven to 375°F. In a large bowl, combine mashed banana, pumpkin puree, and maple syrup.
In a small bowl, combine oat flour, baking powder, salt, cinnamon, and ginger. Combine the wet and dry ingredients. Fold in chocolate chips.
Spoon batter into lined muffin cups and bake for 20 minutes or until the muffins are lightly browned. Remove muffins from the oven and let cool for 5 minutes. Store muffins in an airtight container.