Stoneware, like other forms of pottery, is not structured to handle the temperature shocks of heat and cold at the same time. This presents a challenge when your roasting pan is stoneware and the roast you plan for dinner is still frozen. Increasing cooking time will get your roast done, but you need to prevent your dish from cracking from temperature shocks. Several easy strategies can protect both your dish and your dinner.
Although stoneware is sturdier than some other clays used for cooking utensils, it is still clay. Like glass, it needs to heat evenly throughout or is subject to cracking and breakage. The extreme heat of a hot oven rack combined with the frosty cold of a frozen piece of meat creates shocks that stoneware cannot tolerate. What is needed is a barrier that lets the stoneware and the roast each heat at its own temperature.
One of the easiest barriers is a roaster rack. The metal of the rack can tolerate touching both hot and cold surfaces at once. If you do not have a roaster rack or your rack is too big for your stoneware dish, use a small baking rack, which can keep the weight of a small roast from touching the stoneware surface.
Insulate your roast from its dish with a thick layer of sliced vegetables. Onions, potatoes and carrots are only a few of the possible choices. Sturdy root vegetables create a more solid layer than softer tomatoes, eggplant and peppers, although soft vegetables can be included for added flavor. Oil the baking dish lightly, layer the vegetables and lay your roast on top.
Crumpled Aluminum Foil
For a small roast, wad sheets of aluminum foil to make a mat for your roast. Several slightly flattened balls of foil may be enough to hold a small roast above the pan. You can twist long sheets of foil into a rope and make a figure-eight foil rack for a long or wide roast to sit on.