Preheat the oven to 400F. Put the butter in a 10” oven-safe skillet and put it in the oven until the butter has melted. Swirl the butter to grease the sides of the skillet and set aside.
Stir the corn meal, gluten-free flour, Florida Crystals® Organic Light Brown Raw Cane Sugar, salt, baking powder, and baking soda in a medium mixing bowl until well combined. Make a well in the center and add the buttermilk and egg, then pour in the melted butter from the skillet. Stir until well mixed, then spread the batter in the skillet and smooth the top.
Bake for 20-25 minutes, or until the cornbread is golden brown on top. The cornbread is best served warm with butter.