Preheat your oven to 375°F and place the oven rack in the top third.
Grease a 10-inch cast-iron skillet with softened butter.
In a large bowl, whisk together the flour, cornmeal, baking powder, salt, and sugar.
In a separate bowl, mix the buttermilk, melted butter, and eggs.
Combine the wet and dry ingredients until just mixed.
Fold in the shredded cheese, jalapeños, and creamed corn.
Pour the batter into the prepared skillet.
Bake for 20-25 minutes or until the top is golden brown.