Preheat oven to 400 degrees F. Spray 12 ct muffin pan with non-stick spray or line with muffin cups. Set aside.
Combine wet ingredients until combined.
Gently incorporate dry ingredients - flour, cornmeal, sugar, salt, then baking powder (1 Tbsp).
Mix all ingredients just until moistened. If incorporating additional ingredients, add at this time.
Divide batter between muffin cups, fill to 2/3 full.
Bake for 8 minutes at 400 degrees F; turn heat to 375 degrees F and continue to bake an additional 7-8 minutes - just until done. Avoid over-baking as it will dry out muffins.
Allow to cool before enjoying.