Preheat your oven to 350°F (175°C) and line a muffin tin with silicone liners or grease with a light coating of coconut oil.
In a medium-sized mixing bowl, whisk together the pumpkin puree, large egg, egg whites, and vanilla extract until the mixture is completely smooth.
Add the cinnamon roll protein powder, oat flour, baking powder, ground cinnamon, and sea salt to the wet mixture.
Stir the ingredients together using a spatula until just combined, being careful not to overmix which can make protein muffins rubbery.
Divide the batter evenly into 3 large muffin wells or 6 standard muffin wells, filling them about three-quarters of the way to the top.
Bake for 15 to 18 minutes, or until the tops feel firm to the touch and a toothpick inserted into the center comes out clean.
Remove the pan from the oven and let the muffins cool for at least 5 minutes before removing them from the tin to allow the structure to set.