Air Fryer Red Onions
Air fryer red onions turn soft, sweet and lightly charred at the edges in 12 minutes at 190°C, with only a tablespoon of oil for two large onions. Cut into wedges, they hold their shape and can top burgers, steak, salads or a cheese sandwich. A pinch of thyme and a splash of balsamic vinegar at the end give them extra depth.
- Total
- 20 min
- Prep
- 5 min
- Cook
- 15 min
- Serves
- 4
- Per serving
- 60kcal
Making air fryer red onions ahead
Cook the onions up to 2 days in advance and keep them in a covered container in the fridge. Reheat in the air fryer at 160°C for 3–4 minutes until steaming hot, or serve them cold in salads.
Red onions are sweeter and milder than brown ones, and they keep some colour when cooked. Cut all the wedges to the same size so they are done at the same time.
Air fryer red onions: the method
Tap a time to start a timer.
- Heat the air fryer Preheat the air fryer to 190°C for .
- Cut the onions Peel the onions and cut each lengthways into 8 wedges, leaving a little of the root attached so the layers stay together.
- Season Toss the wedges in a bowl with the olive oil, salt, pepper and thyme until every piece is lightly coated.
- Air fry Tip the onions into the basket in a single layer with a little room between them. Cook at 190°C for , then shake the basket or turn the wedges over.
- Finish Cook for more, until soft and the edges are browned and slightly charred. If you like, toss with the balsamic vinegar straight after cooking and serve warm.
What to serve with air fryer red onions
They are good in a burger, alongside grilled steak or sausages, folded into a warm lentil salad, or piled on a cheese toastie. For another way with onions, pickled pearl onions add a sharp, tangy contrast to the same plate.
If your basket is small, cook the onions in two batches so they brown rather than steam.
Common problems and fixes for Air Fryer Red Onions
- The edges burn while the middle stays firm.
- The pieces are too thin or the air fryer is running hot. Cut thicker wedges, lower the temperature to 180°C and cook for a minute or two longer, checking early.
- The onions come out pale and soft rather than browned.
- The basket was crowded. Cook in two batches of a loose single layer, and finish with 1–2 extra minutes if needed.
- The onions are still crunchy.
- The wedges were cut too thick. Cut them thinner next time, or return them to the basket for 2–3 minutes until tender.
Frequently asked questions about Air Fryer Red Onions
How long do red onions take in the air fryer?
Wedges take 11–12 minutes at 190°C, turning once halfway. Thin slices cook faster, in about 8 minutes.
Can I use white or brown onions?
Yes. Brown and white onions cook the same way, though they are slightly less sweet and the colour is not as striking. For a plain version, see air fryer onions.
Can I cook them in the oven instead?
Yes. Roast the oiled wedges on a lined baking tray at 200°C (180°C fan), gas 6, for 25–30 minutes, turning once, until soft and lightly charred.
Will they turn into deeply caramelised onions?
Not quite, since 12 minutes is too short. They are sweet and soft with browned edges. For jammy caramelised onions, cook sliced onions slowly in a frying pan with a little oil over a low heat for 30–40 minutes.
How did you like the recipe?
4.8 / 5 · 55 ratings
