The Air Fryer Guide: How It Works and What to Cook
An air fryer is really a small, powerful convection oven that blasts hot air around your food to crisp it with a fraction of the oil. It is fast, cheap to run and more versatile than its name suggests, but it also has real limits, and most disappointing results come from ignoring them. This guide explains how it works, what it cooks best, the settings that matter, and how to convert the recipes you already know.
How an air fryer actually works
A heating element sits above the basket and a fan drives hot air down and around the food at high speed. Because the chamber is small, that air is replaced many times a minute, so the surface dries and browns far faster than in a full-size oven. The result mimics deep frying using one or two teaspoons of oil instead of a litre. There is nothing magic about it — it is convection cooking with a very short distance to travel.
What it cooks best, and what it does not
Frozen foods shine: chips, nuggets, spring rolls and dumplings come out crisp without thawing. Vegetables roast well and keep more bite than boiled ones, chicken wings get crackly skin, and it reheats pizza and fried leftovers far better than a microwave. It struggles with wet batters that slide off before they set, with large roasts that need slow even heat, and with leafy greens that simply fly around.
The settings that matter
Most foods cook between 180°C and 200°C (350–400°F). Preheat for three to five minutes, which many models now do automatically, because food added to a cold basket steams before it browns. Never fill past the maximum line: air has to circulate, so a single layer crisps and a piled basket does not. Shake or flip halfway, and start checking two minutes early.
Converting your oven recipes
As a rule of thumb, drop the oven temperature by 15 to 20°C and cut the time by about 20 percent, then check early. A tray of vegetables that takes 30 minutes at 200°C will usually be done in 20 to 22 minutes at 180°C. Small items cook far faster than large ones, and anything with a wet coating takes longer than you expect. Keep notes the first few times; the second attempt is nearly always better.
Oil, starch and browning
You need very little oil, but you do need some. A teaspoon tossed through a bowl of vegetables, or a light spray, gives the surface something to brown. Pat food dry first, because water must evaporate before browning can begin. A dusting of cornflour on potatoes or a pinch of sugar in a glaze deepens the colour. Avoid aerosol sprays, which damage the non-stick coating over time.
Cleaning, safety and when to use the oven
Let the basket cool before washing, and clean it after every use, because baked-on grease turns into smoke next time. Most baskets are dishwasher safe; the main unit just needs a wipe. Do not line the basket with loose parchment or foil, which the fan can draw into the element. For a big roast or a full tray of biscuits, the oven still wins on capacity and evenness.
Frequently asked questions
Do I need oil in an air fryer?
Only a light coating — a teaspoon tossed through, or a quick spray. The hot air does the crisping; the oil mainly helps browning and carries flavour.
What temperature should I use?
180 to 200°C covers most foods. Go lower for delicate items like fish and pastries, higher for quick browning. Air fryers usually need slightly lower temperatures than an oven.
Is air-fried food actually healthier?
It uses far less oil than deep frying, so it is lower in fat and calories while staying crisp. A breaded nugget is still a breaded nugget, though — oil is only part of the picture.
Why is my food not crispy?
Overcrowding, a wet surface, too little oil, or no preheat. Cook in a single layer, pat food dry, toss with a teaspoon of oil and preheat the basket for five minutes before anything goes in.
Can I put foil or parchment in an air fryer?
Yes, with care. Never leave loose parchment in during preheating, since the fan can lift it into the element. Weigh foil down with food and keep the vents clear so air still circulates.