Preheat the oven to 350 F.
In a large bowl, whisk together the pumpkin puree, eggs, oil, coconut sugar, maple syrup, vanilla extract, pumpkin spice and cinnamon until smooth.
Add in the oat flour, salt and baking soda and stir together until evenly mixed.
Line a 12-count muffin tin with paper liners, and pour in about 1/4 cup of batter into each cup, filling it 3/4 of the way. Sprinkle the tops of the muffins with a few rolled oats if desired.
Bake for 22-25 minutes, until firm to touch and a toothpick comes out clean. If adding the sugar glaze, whisk the powdered sugar and water until thick and drizzle it over the muffins once they’re cooled.
Store in an airtight container at room temperature for up to 4 days, or refrigerate for up to two weeks.