Heat the butter in a skillet over medium heat. Add the diced bacon and cook until it starts to crisp. Add the sliced onions and cook slowly for 8 to 10 minutes, stirring often, until soft and lightly golden. Set aside to cool slightly.

In a large bowl, whisk together the flour, baking powder, salt, pepper, and caraway seeds, if using.

In another bowl, whisk the egg, milk, oil or melted butter, and sour cream until smooth.

Add the wet ingredients to the dry ingredients and stir just until combined. Fold in the cooled onion-bacon mixture and the grated cheese.

Preheat the waffle iron and lightly grease it with nonstick spray or oil.

Spoon enough batter into the waffle iron to cover the surface without overflowing, then close the lid and cook until the waffle is deeply golden and crisp, about 4 to 6 minutes depending on your iron.

Remove carefully and repeat with the remaining batter, regreasing the waffle iron as needed.

Serve warm, ideally with a green salad or a dollop of sour cream.