Should I use a glass, ceramic or metal dish in the oven?

Metal browns, glass and ceramic hold heat and are gentle — how the three materials behave differently in an oven and which dish to reach for.

Difficulty: beginner
Time: 7 min
Read: 4 min
Safety: caution

Short answer

Metal conducts fastest and browns best: use it for anything you want crisp — roast potatoes, pastry bases, tray bakes. Glass and ceramic heat slowly and hold heat: use them for anything set gently or served at the table — lasagne, gratins, crumbles, custards. If you swap glass for metal in a recipe, drop the temperature by about 10°C.

The three materials do not just look different, they cook differently, and a recipe that specifies one has usually been tested in it. Knowing the difference tells you when the swap is fine and when it will cost you a soggy base or a burnt edge.

Safety

Glass and ceramic fail by thermal shock — a sudden temperature change of around 40–50°C can shatter them, sometimes several seconds after the change. Never put a hot dish on a cold or wet worktop, never add cold liquid to a hot glass dish, and never take a glass dish from the fridge straight into a hot oven. Ordinary drinking glass and unmarked ceramic must never go in an oven at all.

Step by step

Understand metal: fast, and it browns.Aluminium and steel conduct heat quickly, so the base of the food reaches browning temperature early and stays there. That is what you want for roast potatoes, pastry, pizza, tray bakes and anything that needs a crisp underside. Dark and non-stick metal browns faster still; shiny aluminium reflects and browns more gently.
Understand glass: slow to heat, then it stays hot.Glass conducts poorly but transmits radiant heat, so the food browns more from the top and the sides than from the base. It takes longer to get going and then holds heat well after it comes out, so food carries on cooking on the table. It is the reason a lasagne in glass keeps bubbling for ten minutes.
Understand ceramic and stoneware: slowest and gentlest.The most thermal mass of the three, so it evens out oven fluctuations and heats the food gradually from all sides. Best for anything that curdles or splits if it is rushed — baked custards, gratins, rice puddings — and for anything going straight from oven to table.
Adjust the temperature when you swap.Swapping metal for glass or ceramic: keep the temperature and expect it to take longer, or add 10°C. Swapping glass for metal: drop about 10°C, because the base will brown much faster and can burn while the middle catches up. Either way, watch the edges rather than the clock.
Respect thermal shock in glass and ceramic.Both fail from a rapid temperature change rather than from heat itself. No cold dish into a hot oven, no cold liquid into a hot dish, no hot dish onto a cold granite or wet worktop, no hot dish under a running tap. Put a folded tea towel or a wooden board down before the dish comes out of the oven.
Check the dish is actually ovenproof.Look for an ovenproof or oven-safe mark on the base. Borosilicate glass — the type most older Pyrex is made from — handles thermal change better than the toughened soda-lime glass used in much modern glassware. Unmarked ceramic bought as tableware is not oven safe, and neither is anything with a metallic or lustre glaze.
Match the dish to the depth of the food.Whatever the material, depth drives the timing more than anything else. The same weight of lasagne in a deep narrow dish takes far longer and browns less than in a wide shallow one. Match the dish size to the recipe before you worry about material.

Tips

For a crisp pastry base — a quiche, a pie, a tart — metal every time, and preheat a baking tray under it. Glass insulates the base and is the most common cause of a soggy bottom.
A dark non-stick roasting tin browns considerably faster than a shiny aluminium one at the same setting. If your roast potatoes burn on the base, the tin may be the reason.
Ceramic and glass both go from oven to table, which saves washing up and keeps food hot. Metal loses its heat within a couple of minutes.
Never put an empty glass or ceramic dish into a preheating oven to warm it. It is the one situation where there is no food to moderate the temperature change.

Common mistakes

Adding cold stock or water to a hot glass dish part way through cooking — The inside face cools instantly while the outside stays hot, and the stress cracks it. Warm the liquid first, or use a metal or ceramic dish for anything you will be topping up.
Standing a hot dish straight onto a granite or quartz worktop — The stone draws heat out of the base very quickly, which shocks the dish, and the heat can also damage the worktop. Always use a trivet or a folded towel.

Questions people ask

Can Pyrex go from the fridge into the oven?

No. Any glass dish should come up to room temperature before it goes into a hot oven, and manufacturers say so. Take it out of the fridge while the oven preheats, which is usually long enough.

Why did my glass dish shatter?

Almost always thermal shock rather than a fault — a sudden change of around 40–50°C, most often a hot dish onto a cold or wet surface, or cold liquid added to a hot dish. It can happen a few seconds after the event rather than instantly.

Which is best for a lasagne?

Glass or ceramic. They heat gently, hold heat for serving and give a good browned top under the grill. Metal is fine but cools fast and can react with the acid in the tomato if it is bare aluminium.