Sourdough Onion Rings [simple method only 5 ingredients]
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You're going to love this simple sourdough onion rings recipe. Unlike other recipes, you only need 5 ingredients! Yup, just simple ingredients to make the crispiest onion rings you've ever tasted!
And I bet you've got all of these ingredients in your pantry right now!
The best thing about this sourdough onion rings recipe is that you can use active, fed starter or sourdough discard - it's your choice!
They are easy to whip up on a whim because they really only use pantry staples ... and onions are usually the one vegetable we always have in the house!
These sourdough onion rings make the perfect side dish for these sourdough discard burger buns and these sourdough hot dog rolls. And while you've got the hot oil going, why not make a batch of these sourdough banana fritters, fried sourdough donuts or sourdough elephant ears?
How To Cut Onion Rings
Onion rings are so delicious - and I think it's their simplicity that makes them so good!
For best results, you should cut your onions around ¼ to ½ an inch thick. If they are too thin they will fall apart in the hot oil. Too thick and they will not cook through.
One large onion will serve 3 - 4 people. Now that might seem like a stretch, but once you separate out all the rings, there really will be plenty.
You'd need 2 onions to serve 4 - 6 people.
Take off the outer skin and ends of the onion and use a clever or sharp knife to slice the onion into rings. Be careful not to cut them too thin or they will snap and then won't be actual rings.
Sourdough Discard or Sourdough Starter?
The best thing about this recipe is that you can use either fed sourdough starter or sourdough starter discard.
I would recommend not using sourdough discard that is more than 2 weeks old for the best results.
I like to just feed my sourdough starter a bit more so that I end up with some freshly fed, bubbly starter.
The reason this sourdough batter works so well is that you are using sourdough starter - that is literally flour and water - and adding bubbly seltzer (carbonated) water and baking powder, which gives the batter a little added crispiness.
This is an example of sourdough discard recipe that uses the discard as is - that is there is no further fermentation required.
Sourdough béchamel sauce is made in a similar way.
How To Make Sourdough Onion Rings
These sourdough onion rings really are the ultimate in simple recipes! You literally need just a little soda water and all purpose flour to make them - the baking power is recommended, but certainly not essential!
The hardest thing you'll have to do is heat a pot of oil to fry these onion rings in!
Here's how to make sourdough onion rings:
- Slice your onion into rings and separate all the pieces so you end up with a whole pile. Set them aside.
- Take your sourdough discard, add it to a bowl along with the baking powder and a little of the seltzer (carbonated) water. Use a fork or whisk to thin the discard out until it's like a thin pancake batter.
- Heat the oil you're going to use for frying (you want it between 350F and 375F).
- When you're ready to fry the onion rings, dip the rings into the all purpose flour so they are lightly coated and then into the batter.I do it in batches, so I do a quarter of the rings into the flour and then throw them into the batter.
- Use a fork to transfer the battered onion rings into the hot oil. Let most of the batter drip off before adding them to the oil - the thinner the coating the better!
- Use a scoop to ensure that they are frying evenly and turn them after a minute. They will rise to the top and then go a golden brown. They take around 3 - 5 minutes to cook, depending on the type of oil you're using and the temp you're frying at.
- Remove the onion rings from the hot oil once they're golden brown using a metal scoop. Pop them on some paper towel to drain before serving.
- Sprinkle with salt if desired.
Best Tips For Frying Sourdough Onion Rings
While this is a super easy recipe, the way you fry the onion rings will make all the difference to your end product.
Here are my best tips for frying sourdough onion rings:
- Do not over batter the onion rings - thinner batter is better because you only want a really thin coating. This will ensure crispy onion rings that don't become soggy.
- Make sure you use clean oil that hasn't been used for frying other things.
- Don't overcrowd the oil - I work on doing a quarter of the onion rings at a time. If you overcrowd the pan they will stick together and the temperature of the oil will drop making your onion rings soggy.
- Make sure your oil is hot enough before you add the onion rings. It needs to be 350F - 375F (176C to 190C). If it's not hot enough, the oil will seep into the onion and they will be soggy. Similarly, if it's too hot, the batter will burn and the onion will be raw in the middle. You can use a thermometer to ensure your oil is at the right temperature.
- Use a metal scoop or spider scoop to move the onion rings around and take them out of the hot oil. These are also great for boiling bagels!
What Type of Onions Make The Best Onion Rings
Yellow onions are the ones you need for onion rings. They may also be called brown onions (in Australia). They are a sweeter onion than a red or white onion.
You don't want to use anything too pungent to make these onion rings.
What Kind of Pan Should You Use To Fry Onion Rings In?
I have used my Dutch Oven that I use to make sourdough bread with to fry these onion rings. I fill it with 2L of oil and this gives me plenty of room for the onion rings to fry without sticking together.
You could also use a deep fryer.
You don't want to use too shallow a pan or you won't have enough room for the onions to fry.
What Oil Is Best for Frying Onion Rings?
For this recipe I have used basic vegetable oil. You want a light flavored oil that won't impart any flavor onto the onion rings. You also need to choose an oil with a high smoke point - above 375F (176C).
I would recommend the following oils:
- Vegetable Oil
- Rice Bran Oil
- Canola Oil
- Peanut Oil
Do not use olive oil!
What Water To Use For Your Sourdough Batter?
In this recipe I have used "Seltzer" water but it may be known as carbonated water, soda water or even sparkling water depending on where you're from.
It's fizzy, gassy water full of lovely bubbles!
I just use Seltzer water I make in my soda stream maker - nothing else added - just injected with carbon dioxide gas.
You can use any type of Seltzer or carbonated water you can buy from the store.
You can also substitute beer for the carbonated water. I recommend a light flavored beer, icy cold. This will give your sourdough onion rings a deeper flavor. You might also like to try making this sourdough beer bread.
"Beer batter" works really well for fish too (I learned to make it this way from my Dad!).
Can You Cook Sourdough Onion Rings In An Air Fryer?
No, these sourdough onion rings aren't suitable for cooking in an air fryer. Because they are battered, you need hot oil to crisp up and cook the batter.
You could possibly reheat the onion rings in an air fryer however I have not tried this.
Air fryers are better suited to onion rings that have been coated in bread crumbs, rather than those coated in batter.
Want to Make Your Sourdough Onion Rings Pop?
While this recipe is delicious in its simplicity, there are a few things you can do to add more flavor to your onion rings or jazz them up to serve for company:
- Sprinkle with seasoned salt and serve with a dish of Kewpie Mayonnaise blended with Srirachia Hot Sauce. Out of this world delicious! This is how I've served the onion rings in the photos here.
- Add a teaspoon or 5g of curry powder to your sourdough batter. This also adds a lovely color to your onion rings.
- Add a teaspoon or 5g of mustard powder to your sourdough batter.
- A teaspoon or 5g of cayenne pepper added to your batter is great for a kick!
- Serve salted onion rings alongside ranch dressing, blue cheese dressing, salsa or your fave avocado dip for an appetiser that's sure to please!
What Else Can I Use This Sourdough Batter For?
You can use this sourdough batter to coat and cook many things. Think crispy fried chicken and tempura vegetables! You can find a step by step guide to sourdough discard batter here.
Here are some other ways to utilise this sourdough batter - you might just need to double the quantity for some things:
- Crispy Fried Chicken - dredge the chicken pieces in seasoned flour and then dip into the sourdough batter and then into the hot oil.
- Tempura Vegetables - dredge the veggie pieces into seasoned flour and then dip into the sourdough batter and then into the hot oil.
- Fried Potato Scallops - slice a few potatoes into thin slices using a mandolin, dredge in seasoned flour and then dip into sourdough batter. Fry in hot oil.
Frequently Asked Questions
Sourdough starters are super easy to make - they just require a bit of patience. You can find simple instructions for making sourdough starter here. But if you'd prefer to buy one, I recommend going here.
You can use a sourdough starter or sourdough discard for this recipe - whatever you have on hand is fine. I would recommend not using sourdough discard that is more than 2 weeks old for this recipe. Fed, bubbly sourdough starter will give you the crispest, crunchiest and tastiest batter.
This recipe uses 100g of sourdough starter or sourdough discard, which isn't a tonne, however if you maintain a smaller starter you might need to feed your starter a bit extra to have enough. You'll find instructions for increasing your sourdough starter here.
There are two things you should do to ensure the batter sticks to your sourdough onion rings. Make sure that the soda water you use is cold. Also, ensure that you dust them in all purpose flour before you dredge them into the sourdough batter. This will make sure that the batter sticks to the onions and does't come off when the rings hit the hot oil.
You should aim to have the oil at 350F to 375F or 176C to 190C. You don't want it outside these parametres or you will undercook or burn the onion rings. Oil that isn't hot enough will also result in soggy onion rings.
I have used 2L of vegetable oil in a 4L Dutch Oven. You want to make sure that the onion rings aren't crowded in the pot or they will stick together.
There are usually two main causes for soggy onion rings - you've either not got the oil hot enough (use a thermometer to make sure) or you've used too much batter. The onion rings only need a really light coating of batter. Too much batter will mean that it will retain too much moisture after cooking. When you remove them from the hot oil this moisture will start to seep out.
Carbonated water (like seltzer or soda stream water) is great for making batter because it is bubbly and fizzy. These bubbles, caused by artificially injecting the water with carbon dioxide gas, give you a light, bubbly batter that crisps up really well in hot oil.
Want More Recipes?
If you're loving these sourdough onion rings, you might enjoy these sourdough recipes:
- Sourdough banana fritters are fried in hot oil, just like onion rings!
- Onion rings are a great accompaniment to Sourdough Hot Dog Buns and Sourdough Discard Hamburger Buns!
- Sourdough Brioche Rolls (perfect for burgers).
Sourdough Onion Rings Recipe
Equipment
- Large Pot of Oil or Deep Fryer
Ingredients
- 1 Large Yellow Onion brown onion
- 100 g Sourdough Starter can be discard
- 50 g Seltzer Water carbonated water or soda water (see notes)
- 6 g Baking Powder
- 100 g All Purpose Flour for dusting
For Frying
- 2 L Vegetable Oil for frying
- 20 g Salt for sprinkling
Instructions
- Slice your onion into rings around ¼ to ½ inch thick and separate all the pieces so you end up with a whole pile. Set them aside.
- Take your sourdough discard, add it to a bowl along with the baking powder and a little of the soda water. Use a fork or whisk to thin the discard out until it's like a thin pancake batter.
- Heat the oil you're going to use for frying (you want it between 350F and 375F or 176C and 190C) - see notes in post above for options on pans and oils.
- When you're ready to fry the onion rings, dip the rings into the all purpose flour so they are lightly coated and then into the batter.I do it in batches, so I do a quarter of the rings into the flour and then throw them into the batter.
- Use a fork to transfer the battered onion rings into the hot oil.
- Use a scoop to ensure that they are frying evenly and turn them after a minute. They will rise to the top and then go a golden brown. They take around 3 - 5 minutes to cook, depending on the type of oil you're using and the temp you're frying at.
- Remove the onion rings from the hot oil once they're golden brown using a metal scoop. Pop them on some paper towel to drain before serving.
- Sprinkle with salt if desired.
Notes
Nutrition
