Preheat oven to 400 degrees Fahrenheit. Grease a 12 cup muffin pan and set aside.
In a large bowl, whisk together the dry ingredients - cornmeal, flour, sugar, baking powder, baking soda, and salt. Make a well in the center of your dry ingredients.
Add the buttermilk, melted butter, and eggs to the dry ingredients and mix until just combined (stop mixing as soon as you don't see any streaks of dry ingredients anymore).
Portion batter between 12 muffin tins. Bake for about 11-13 minutes, or until toothpick inserted into center comes out with a few crumbs, and/or the tops of the muffins bounce back right away when gently pressed with a finger.
Allow to cool for up to ten minutes before removing muffins from the pan. As they cool, they will contract from the sides of the pan, making them easier to remove. If needed, use a butter knife to gently pop your muffins out of the pan.
Optionally, brush the tops with melted butter before serving.
Muffins are best served same day, and leftovers enjoyed within two days of preparing.
If you're opposed to adding a small amount of sugar to your muffins, feel free to omit it.
Leftover muffins can be frozen and thawed for future meals. Once muffins are cooled to room temperature, wrap in wax paper or foil, then store in a freezer-safe bag or tightly sealing container. Bread will keep for 3 to 6 months when stored properly.
Buttermilk substitute - in a liquid measuring cup, add 1 tablespoon of lemon juice or white vinegar. Fill with milk (to the 1 cup line), then allow to set for 5 minutes. This will curdle your milk, creating a buttermilk substitute.