Make these Sourdough Onion Rings to accompany burgers at your next barbecue or as a fun snack when you get together with friends or family to watch a sports game. Covered in a rich sourdough batter, the onions slices are fried in olive oil on both sides until crisp and golden. Serve with ketchup, barbecue sauce, or your favorite dipping sauce. You can easily make your own sourdough starter, there are hundreds of recipes on the internet that will walk you through the process.