Glass, Metal or Ceramic: Choosing a Pie Plate

The dish under your crust affects browning, timing and even safety. Here is how the three common materials compare, and how to bake well in each.

Two bakers can follow the same recipe and get different pies, and the pie plate is often the reason. A pale, soggy bottom crust in one kitchen and a deeply browned one in another usually comes down to how the dish moves heat into the dough. You do not need a cabinet full of plates, but it helps to know what each material does.

How the materials handle heat

Metal, especially aluminum, conducts heat quickly. The crust starts cooking almost as soon as the plate hits a hot oven, which sets the bottom and browns it well. The tradeoff is speed: a dark or heavy-gauge metal pan can brown the edges before the filling is ready, and a very thin pan can scorch.

Glass conducts heat more slowly than metal, but once it is hot it holds that heat well. It also lets some radiant heat pass straight through, so the bottom crust often browns steadily and evenly, just a little later than in metal.

Ceramic and stoneware are thick and slow to heat. They take longer to get going, then hold a steady temperature, which is gentle on custard and cream fillings. They are heavy, and they are often the most attractive plates to bring to the table.

Why many bakers like glass

The biggest advantage of glass is that you can see what is happening. Lift the plate and look underneath: a golden-brown bottom means the crust is done, and a pale one means it needs more time. For a new baker, or anyone making a juicy fruit pie, that check removes a lot of guesswork. Because glass stays hot, it also keeps the pie warm longer on the table, so the filling continues to set slightly after it leaves the oven.

Glass safety and thermal shock

Glass can crack or shatter when part of it changes temperature much faster than the rest. This is called thermal shock. A few habits prevent it:

• Never put a hot glass plate on a wet counter, a cold stone surface, or in the sink. Set it on a dry towel, wooden board or wire rack.
• Do not move a plate straight from the freezer to a hot oven unless the maker's instructions say that is safe. Many say it is not. Let a frozen pie sit a short while first, or bake it in a metal plate.
• Do not pour cold liquid into a hot dish.
• Do not use glass under the broiler or on a stovetop burner unless it is specifically made for that.
• Check for chips, cracks or deep scratches before each use. A damaged plate is more likely to break, so retire it.

Ceramic can be sensitive in similar ways, so follow the directions that came with your plate. Metal is the simplest choice for a pie you plan to freeze and bake straight from the freezer.

Standard vs. deep-dish: size and volume

Plate sizes are measured across the top, rim to rim, so two plates both called "9-inch" can hold different amounts. A standard 9-inch (23 cm) plate is about 1 to 1 1/4 inches (2.5 to 3 cm) deep and holds roughly 4 cups (about 950 mL) of filling. A deep-dish plate of the same width is usually 1 1/2 to 2 inches (4 to 5 cm) deep and holds about 5 to 6 cups (1.2 to 1.4 L).

Using the wrong one causes problems. Pour a recipe written for a deep dish into a standard plate and the filling will overflow in the oven. Do the reverse and the pie will look short and flat. Many recipes do not say which they assume, and sizes are not perfectly standard from one plate to the next.

The easy fix is to measure your own plate. Fill it to the rim with water, one cup at a time, and count. A fruit pie should be filled to just below the rim before baking, and a custard pie to about 1/4 inch (6 mm) below it. If your plate holds more than the recipe expects, make a little extra filling; if it holds less, bake the leftover filling in a small ramekin so the pie does not overflow.

Adjusting bake times and temperature

Most pie recipes are written with one kind of plate in mind, usually glass or light metal. If you are using something else, these adjustments are good starting points. Always trust the visual and physical signs over the clock.

• Glass: If a recipe was written for metal, lower the oven by about 25°F (about 15°C) to keep the edges from browning too fast, and expect it to need a few extra minutes.
• Dark or thick metal: Check 5 to 10 minutes early. Shield the rim with foil if it is already deep brown.
• Ceramic: Allow 5 to 10 minutes more, and use the lower rack with a preheated baking sheet so the bottom crust does not stay pale.
• Deep-dish: Plan on 10 to 15 minutes more than a standard pie, since there is more filling to heat through. Fruit pies should bubble thickly in the center, and custard pies should be set around the edges with a slight wobble in the middle.

Ovens vary, so write down what works. If you bake the same pie twice in different plates, note the time and temperature each time.

Which one should you buy?

If you only want one plate, a standard 9-inch glass plate is a sensible first choice because you can check the crust, and it works with the widest range of recipes. If you like a crisp bottom and often bake fruit pies, add a light-colored metal plate. If you care about presentation or bake a lot of custard pies, a ceramic plate is a nice addition. A deep-dish version of whichever you pick is useful for the big fall apple pie.