Vegetables
Onions
A short cook on direct heat, and the cut decides everything: halves collapse sweetly, slices char at the edges.
What it does in fast-moving hot air
An onion is layered sheets of high-water cells separated by thin membranes, and heat travels along the layers far better than across them. A halved onion presents a large flat cut face that caramelises while the layers behind it steam in their own moisture and go sweet. A slice is mostly edge, and edges are thin, dry fast and go from caramel to bitter in about a minute — which is why the published temperature for slices is one level lower than for halves. Loose rings are also the classic food a fan lifts and throws at the element.
Why the cut matters
Onions are in the catalogue as a cooked vegetable in their own right rather than as an ingredient, because the published guidance treats them that way: halves and slices get different temperatures and different times in the same chart.
Cooking pages
- Onion halves — One manufacturer grills six halved onions weighing 600g for five to seven minutes; it does not say fresh or frozen.
- Onion slices — One manufacturer grills 2.5cm slices for six to eight minutes, one plate setting below halves; it does not say fresh or frozen.
This page gives no cooking answer of its own. A food does not have one — a cut, at a thickness, in a state, at a loading, in a particular appliance does. Any figure mentioned above is one manufacturer’s, and the page for the cut says which machine, quantity and state it was printed for, or that the manufacturer named no state.