Preheat oven to 350°F, and place butter into an 8-inch cast iron or oven-proof skillet.

Place the skillet in the preheated oven, and allow the butter to melt while you prepare the remaining ingredients.

In a large bowl, mix together flour, cornmeal, baking powder, and salt. Set aside.

In a separate medium bowl, combine egg, milk, and buttermilk.

Add the wet ingredients to the dry ingredients and stir to combine. Carefully stir in the melted butter, then fold in jalapenos and cheese.

Scoop the batter into the hot skillet. Bake for 45 minutes, or until a toothpick inserted in the center comes out clean.

Serve immediately with extra butter or honey. See post for storage options.