When it's impractical to use the temperature advised in a recipe, such as an 800-degree oven used for baking pizza, home cooks can sometimes produce similar results by changing the cooking time accordingly. However, success varies from one dish to the next, so it's advisable to give your experiment a test run before serving it to company. No hard-and-fast rules apply to all foods, so you may need to experiment by trial and error to adapt a specfic dish.
Increase the cooking time for a lower temperature and decrease the cooking time for a higher temperature. Avoid extreme changes in either temperature or time; the more you vary from the original recipe, the less your dish will resemble the intended result. Avoid tampering with baked recipes, as the delicate interactions of proteins and carbohydrates are highly influenced by temperature and timing.
Consult alternate recipes of the same dish for variations in cooking time and temperature. Check whether the alternate recipes have different ratios of wet and dry ingredients. Adapt your recipe as necessary. Expect greater evaporation of liquids at higher temperatures, but less opportunity for ingredients to "set" with shorter cooking times.
Check internal temperatures for doneness whenever appropriate. Cook poultry to an internal temperature of 165 degrees Fahrenheit and cook ground meats to 160 degrees Fahrenheit. Let hams and roasts, steaks or chops of beef, pork, lamb or veal all reach at least 145 degrees Fahrenheit. Cook casseroles and egg dishes until they reach at least 160 degrees Fahrenheit and heat stuffing or general leftovers to an internal temperature of 165 degrees Fahrenheit.
Check on foods' internal temperatures regularly if you have increased the temperature; begin checking shortly after the recommended cooking time if you have decreased the temperature.
Allow for unusual conditions, such as high altitudes. Increase the cooking temperature of oven-baked goods by 15 to 25 degrees Fahrenheit and reduce the cooking time by five to eight minutes for every 30 minutes of recommended baking time, if you live at an altitude of 3,000 feet above sea level.
Allow for some variation in the finished product, depending on how you adapt the temperature and timing. Expect a crustier loaf of bread if you increase the oven temperature and a pillow-like texture if you reduce the temperature. Select a lower oven temperature if you prefer crispy, flat cookies. Keep the oven hotter and cook for less time if you prefer a chewy texture and a thick cookie.