First, preheat to 180 degrees Celsius (350ºF) and spray muffin forms with coconut oil cooking spray.
Place all dry ingredients in a large bowl and mix until combined (except blueberries). Then, add all wet ingredients (except the coconut oil) and mix until smooth. Last, add melted coconut oil and blueberries and mix again.
Source: Fit Quick Recipes
Transfer batter into muffin forms and bake for about 30-30 minutes.