Pour the buttermilk into a small bowl, add the baking soda, stir to combine. Add the buttermilk/baking soda mixture to the pan with the melted butter, stir to combine . Add the cornmeal and flour into the pan, whisk until incorporated and there are few (if any) lumps in the batter. Pour the batter into your prepared pan. Sprinkle crumbled bacon over top of the batter. Bake 25 to 30 minutes until golden brown and tooth pick comes out clean.