Preheat oven to 400o F. Line 12 muffin cups with paper liners, or grease muffin cups.
Mix dry ingredients in one bowl, except nuts. Blend wet ingredients in another bowl. Add wet ingredients to the dry mixture and mix just until blended and there are no dry pieces. Do not over mix; batter will be thick. Gently fold in nuts, if using.
Spoon into prepared muffin cups. Sprinkle with cinnamon. Bake 20-22 minutes or until golden brown.
Note: Keep in sealed container in cool place for up to 3 days.