What to look for
- Heavy gauge
- Thin trays buckle in a hot oven — the bang you hear is the tray warping — and food slides into the resulting dip. Heavy trays stay flat and heat evenly.
- Pale, not dark
- Dark metal absorbs radiant heat and browns the underside much faster. Good for pizza bases, bad for biscuits and cakes, which scorch underneath.
- A low rim on at least one side
- A completely flat sheet lets you slide things off; a rim stops fat running into the oven. One of each is ideal.
- Aluminium or aluminised steel
- The best conductors at a domestic price. Stainless is durable and conducts less well.
- Not non-stick
- Non-stick coatings on trays wear quickly under scraping and limit oven temperature. Parchment does the same job better.
- Fits your oven
- With at least a couple of centimetres of clearance all round. Air must circulate or nothing browns evenly.
How many you need
- Two large heavy sheets, the same size, is the practical minimum. Two is what lets you spread roast vegetables out rather than crowding one.
- A third is useful for batch baking, where one cools while another bakes.
- One deeper roasting tin, separately, for anything producing a lot of fat or liquid.
- A wire cooling rack that fits inside one of them, which turns a tray into a roasting rack, a draining rack and a reheating rack.
Using them well
- Preheat the tray for roast potatoes, roasted vegetables and anything you want to crisp underneath. Food hitting a hot surface starts browning immediately.
- Do not preheat for biscuits and pastry, which need to hold their shape before the fat melts.
- Parchment for baking, bare metal for browning. Parchment insulates slightly and reduces contact browning.
- Do not crowd. The commonest error, and the reason vegetables steam. See crowding suppresses evaporation.
- Rotate the tray halfway through. Every domestic oven has hot spots.
- Do not cut on it, and do not scrape burnt sugar off with metal.
Why a warped tray matters more than it seems
When a thin tray warps, it stops making even contact with the oven shelf and its own surface stops being flat. Oil pools in the low spots and runs away from the high ones, so food on one side fries in fat and food on the other dries out.
It also means the tray flexes as it heats and cools, which is where the alarming bang comes from. A heavy-gauge tray simply does not do this, and it is the main reason to spend a little more.
A warped tray cannot be flattened reliably and is worth replacing. It is one of the cheapest meaningful upgrades in a kitchen.
Common questions
Can I use foil instead of parchment?
Yes, though foil conducts heat and browns the underside more. Shiny side down reflects slightly less. Acidic foods can react with foil.
Why do my biscuits burn underneath?
A dark tray, an oven shelf too low, or a tray that was preheated. Use a pale tray in the middle of the oven.
Are silicone mats worth it?
For biscuits and anything sticky, yes — they last for years and give very even results. They do insulate, so they reduce browning underneath.
How do I clean a badly stained tray?
Bicarbonate of soda and a little water into a paste, left for an hour. Staining is cosmetic and does not affect performance.
Try this next
- Roasting tin the deeper relative
- Baking oven behaviour
- Roast vegetables not browning why two trays beat one
- Biscuits where tray colour shows