Preheat the oven to 375°F. Cook the bacon in a 10-inch cast iron skillet over medium heat, turning occasionally, until crisp, about 8 minutes. Transfer the bacon to paper towels to drain and cool, then crumble the bacon. Add the butter to the hot bacon fat to melt, then pour it into a large bowl and let cool for 10 minutes; don’t wipe out the skillet.

Stir the creamed corn into the melted fats along with the buttermilk, eggs, cheeses, jalapeños, and the crumbled bacon. Combine the cornmeal, sugar, baking soda, salt, and pepper in a separate large mixing bowl. Add the wet ingredients to the dry and stir until incorporated. Pour the batter into the skillet and bake until the top is lightly browned and the center is set, 30-35 minutes.

Let the cornbread cool slightly, then slice and serve.