Preheat the oven to 450°F. Coarsely chop the bacon. Cook the bacon in a 10 to 12-inch cast iron skillet over medium-high heat. Cook until the bacon is just crisp. Remove from the heat. Do not drain the grease away.

In a medium bowl, combine the cornbread mix and milk and stir until combined. Pour the batter into the hot skillet over the bacon and bacon grease. Carefully spread even, then bake for 16 to 18 minutes or until golden brown. Remove from the oven and invert on a plate to remove the cornbread from the pan. Serve warm.