# Onions cooking times

How long to cook onions: **8–10 min pan-fried, 30–40 min in the oven at 200°C (180°C fan), 10–12 min in an air fryer at 190°C and 2–3 min deep-fried at 180°C**. Every way to cook it is below, with the temperature and how to tell it’s done.

Source: https://feastflow.co.uk/onions-cooking-times (FeastFlow free cooking-time guides). Last checked 11 November 2026.

## How long to cook onions

Times are for 2 large onions, for 4.

Onions: cooking times by method:

| Method | Time | Heat | How |
| --- | --- | --- | --- |
| [Pan-fry](https://feastflow.co.uk/pan-frying-times) (Softened) | 8–10 min | over a medium heat | Fry in oil or butter, stirring often, until soft and translucent. |
| [Pan-fry](https://feastflow.co.uk/pan-frying-times) (Caramelised) | 35–45 min | over a low heat | Caramelised: cook slowly in butter and oil, stirring every few minutes, until deep golden. It can’t be rushed. |
| [Oven](https://feastflow.co.uk/oven-cooking-times) (Wedges) | 30–40 min | 200°C (180°C fan), 400°F, gas 6 | Wedges tossed in oil. |
| [Air fryer](https://feastflow.co.uk/air-fryer-cooking-times) (Wedges) | 10–12 min | 190°C (375°F) | Wedges or thick slices, tossed in a teaspoon of oil. |
| [Deep-fry](https://feastflow.co.uk/deep-frying-times) (Rings) | 2–3 min | oil at 180°C (350°F) | Onion rings, battered or floured. |
| [Barbecue](https://feastflow.co.uk/bbq-cooking-times) (Thick slices) | 8–10 min | over medium direct heat | Thick slices brushed with oil; turn once. |
| [Microwave](https://feastflow.co.uk/microwave-cooking-times) (Softened) | 4–5 min | on full power | Sliced, with a knob of butter, to soften quickly before frying. |

## Before you start

Peel, halve and slice, or cut into wedges through the root so they hold together.

## How to tell it’s done

Softened onions are translucent and floppy with no colour; caramelised onions are deep brown, sticky and sweet.

## Questions

### How long to pan-fry onions?

Softened: 8–10 min over a medium heat. Fry in oil or butter, stirring often, until soft and translucent. Caramelised: 35–45 min over a low heat. Caramelised: cook slowly in butter and oil, stirring every few minutes, until deep golden. It can’t be rushed.

### How long to cook onions in the oven?

Wedges: 30–40 min at 200°C (180°C fan), 400°F, gas 6. Wedges tossed in oil.

### How long to cook onions in an air fryer?

Wedges: 10–12 min at 190°C (375°F). Wedges or thick slices, tossed in a teaspoon of oil.

### How long to deep-fry onions?

Rings: 2–3 min in oil at 180°C (350°F). Onion rings, battered or floured.

### How long to barbecue onions?

Thick slices: 8–10 min over medium direct heat. Thick slices brushed with oil; turn once.

### How long to microwave onions?

Softened: 4–5 min on full power. Sliced, with a knob of butter, to soften quickly before frying.

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Times are a guide for typical home portions: ovens, air fryers, microwaves and sizes vary. Check meat, poultry and fish with a thermometer. Safe temperatures follow USDA and UK Food Standards Agency guidance.

FeastFlow also plans a whole meal backwards from serving time, with every dish timed and oven temperatures that don’t clash: https://feastflow.co.uk/