This article was updated on 3rd July 2023 for clarity and freshness.
Onion rings are always best fresh out of the fryer (I think we all know that). But what happens if you’ve made just a few too many and don’t want to waste them?
In this article, I personally test every onion ring reheating method I could find, to let you know the best way to keep your leftover onion rings crispy and flavorful.
In a hurry?
The best way to reheat onion rings is in the oven. Place the onion rings on a pre-heated baking tray and lightly spray them with oil. Reheat the onion rings for 5-7 minutes at 350°F (180°C) or until piping hot. Serve the onion rings immediately for best results.
How we tested the reheating methods
I made my own onion rings at home following this recipe (they’re way better than the store-bought stuff, you should try it!) and kept them in the fridge overnight.
The next day I reheated them using 5 different methods. I tested:
- In the oven: Decent results, easy, and reliable.
- By broiling: Crispy and delicious.
- In the air fryer: Your best bet if you own one.
- Re-frying: Okay, but easy to overdo them.
- In the microwave: Never do this.
For each method, I tasted the onion rings and took notes on their appearance, flavor, and texture. Crispness was a particular focus.
How to reheat onion rings in the oven (or toaster oven)
Time: 5-7 minutes
- Preheat your oven to 350°F (180°C) with the baking tray inside the oven.
- Put the onion rings on the hot baking tray and spritz them with a light coating of oil.
- Optional: sprinkle some extra flavoring on the onion rings like parmesan or garlic powder to give them a little boost.
- Put the onion rings in the oven and heat them for 5-7 minutes (3-5 minutes will be enough in a toaster oven).
- Serve immediately.
The idea behind preheating the baking tray too is so the bottom of the onion ring doesn’t become soggy. You can also place the onion rings straight on a wire rack, but you might end up with a few crumbs in the bottom of your oven.
I also tested microwaving the onion rings for 5 seconds before putting them in the oven to heat the middle (advice I saw on another site). But I wasn’t impressed with the results, the batter was too chewy and it only saved around a minute of time.
This trick works better for thicker things like onion bhajis (yes, that links to my reheating experiment on onion bhajis, feel free to check it out!).
Results: The oven is hassle-free, easy, and gave me decent (but not amazing) results. The onion rings were crispy, but not as crispy as the day before, and you could still taste the onions.
How to reheat onion rings under the broiler
Time: 4 minutes
- Lay the onion rings flat in a single layer and spritz them lightly with oil.
- Place the onion rings under a medium-hot broiler and heat them for 2 minutes.
- Flip the rings over and heat for an additional 2 minutes on the other side.
- Serve immediately.
The flip halfway through makes sure both sides crisp up.
I always put a layer of tin foil under the rack to catch any oil that drips off. This saves you from having to clean the grill every time.
Psst… if you don’t have a pair of kitchen tongs, now is the time to invest. Tongs makes flipping the onion rings so much easier.
Results: The broiler gave pretty similar results to the oven but the rings were definitely crispier. Overall, I’d say I enjoyed the onion rings from the broiler more than I did the oven but it was more effort because I had to flip the rings halfway through.
How to reheat onion rings in an air fryer
Time: 3-4 minutes
- Set your air fryer to 350°F (180°C).
- Lightly coat your onion rings in oil.
- Put the onion rings in the air fryer for 3-4 minutes.
- Serve immediately.
A light spritz of oil gives the onion rings that ‘fresh-out-of-fryer’ taste and helps them crisp up. But if your onion rings are already greasy, you can skip it.
A few minutes in the air fryer will be more than enough to heat your onion rings all the way through. If you leave them for any longer you risk the onion rings drying out or the onion becoming non-existent (and leaving what feels like just a ring of batter).
Results: One of the best options here. You get all the crispness of the fryer with less risk of the rings becoming a hollow shell, and it’s quick and easy. The only downside is you need an air fryer, which not everyone has!
How to reheat onion rings by re-frying
Time: 5 minutes (including time to heat the oil)
- Heat 1-2 inches of vegetable/canola oil in a pan until it reaches 350°F (180°C). If you don’t have a thermometer, drop a breadcrumb in the oil. If it sizzles immediately, the oil is ready.
- Place the onion rings in the oil for 2-3 seconds.
- Flip the rings over with tongs and cook them for another 2-3 seconds.
- Take the onion rings out and put them on a wire rack to let any excess oil drip off.
- Serve immediately.
Note: you can also deep fry the onion rings in more oil, in which case you won’t need to flip them. Or use less oil if you’re worried about the onion rings being too greasy.
A few seconds might not seem like a long time, but trust me it’s all you need. You aren’t trying to cook the rings again, just heat them up. Three seconds in 350-degree oil is more than capable of heating up a small onion ring.
If you leave the onion rings for too long, they’ll quickly overcook and turn into burnt hollow shells… you’ve been warned. You also need to watch out for oil that’s too cold. If the oil isn’t sizzling when you drop the onion rings in, the batter will soak up all of the oil and become super greasy. Yuk.
Psst… a trick I read on a forum was to re-batter the onion rings before frying them – but I feel this would throw the batter-onion ratio off.
Results: My refried onion rings were super crispy, much more crispy than any other method I used. But there wasn’t much onion left inside them because it had dried up from the heat. Avoid this method if you have really thin onion rings (as I did), or your onion rings are already slightly overdone. If you have thick rings, or they’re slightly underdone, this is a great method.
Bonus method: reheating onion rings in the toaster
The toaster is an interesting option for on-the-go heating. When you’re at work you often only have a toaster or a microwave. Microwaves are a no-go for onion rings (you’ll see why later), so that leaves the toaster as a potential option.
But you need toaster bags. They make sure the onion rings don’t drip any grease into the bottom of the toaster, as well as making sure they don’t get stuck. There’s nothing worse than putting something in the toaster only to find it’s too small to get out again.
Results: I tested this one as a bit of an afterthought, so didn’t get pictures and it was okay. The onion rings heated up but they didn’t get particularly crispy. I guess the bag trapped some steam which stopped them crisping up.
Avoid the microwave (at all costs)
Microwave reheated onion rings are soggy, limp, and greasy. Exactly the opposite of how you want an onion ring to be. Microwaves just can’t deal with crispy food.
I tested it so I could give an accurate picture of the taste and texture of the onion rings and I can safely say I will never use the microwave to reheat onion rings again.
To make matters worse, after a minute or so, the onion rings had started to cool down and became so tough and chewy that it was hard to believe it was the same onion ring. It was like eating cardboard.
Avoid. Avoid. Avoid.
How to keep onion rings warm and crispy
To keep onion rings warm and crispy, put them in a warm oven (200°F/90C°) and close the door. Lay the onion rings in a single layer on a wire rack and don’t cover them. Covering the onion rings will create steam and leave them soggy.
You can place a tray underneath the wire rack to catch any drops of grease.
The oven is the best place to keep the onion rings warm because it uses dry heat and won’t introduce any moisture. Keep the door closed as much as possible to stop moisture getting into the oven from outside, and avoid putting anything else in the oven apart from the onion rings.
You don’t want moisture to transfer from another dish to your onion rings.
You can keep the onion rings warm this way for up to an hour. After this, the onion rings will start to dry out and become tough. If you need to store the onion rings for more than an hour, I suggest storing them and then reheating them just before serving.
How to store onion rings
To store onion rings, let them cool to room temperature and then place them in an airtight container lined with paper towel. Arrange the onion rings in a single layer, separating layers with more paper towel. Keep the onion rings in the fridge for 3-4 days.
The paper towel helps to soak up excess grease and moisture. If you pile all the onion rings on top of one another, they’ll get very soggy.
Can you freeze onion rings?
Homemade onion rings that have only been cooked once are good candidates for freezing. But pre-cooked onion rings that you’re freezing for a second time won’t freeze as well.
To freeze onion rings, cool them to room temperature and spread them out on a parchment paper-lined baking tray. Freeze them on the baking tray for 30-45 minutes. Once frozen, transfer them to a freezer bag, suck all the air out, and leave them for up to 3 months.
If you know in advance that you’re going to freeze the onion rings it’s best to undercook them by around a minute. This ensures that they won’t overcook or burn if you plan on re-frying them. Par-cooking them is less important if you want to reheat them in the oven.
You can also freeze homemade onion rings before you’ve cooked them. Simply blanch the raw onions for 10-15 seconds in boiling water before submerging them in ice-cold water to stop the cooking.
After blanching the onion rings, batter them as you normally would, then follow the instructions above. If you don’t blanch the raw onions, they’ll get very soft and mushy in the freezer.
There’s no need to thaw the onion rings before you cook or reheat them. You can heat them straight from frozen, just allow them slightly longer.
Read Next: How To Reheat Calamari
Exactly How To Reheat Onion Rings [Tested Methods]
- Paper towel
- Wire rack
- 1 portion onion rings
- 2 sprays oil optional
- Preheat your oven to 350°F (180°C).
- Put the onion rings on a baking tray and spritz them with a light coating of oil.
- Sprinkle some extra flavoring on the onion rings like parmesan or garlic powder to give them a little kick (optional).
- Put the onion rings in the oven and heat them for 3-5 minutes or until they’re warmed through.
- Serve immediately.
- Re-frying onion rings (okay, but easy to overdo them)
- Reheating onion rings in the oven (probably the best option out of the bunch)
- Reheating onion rings in the microwave (seriously, never do this)
- Reheating onion rings by broiling (nice enough)
- Reheating onion rings in the air fryer (your best bet IF you own one)