Foil is important to the cooking process of lasagna as well as other casserole-like dishes. While it does not necessary speed up the cooking process, it does assist the getting the temperature high enough to get the sauce boiling and cook the lasagna while not allowing the valuable moisture to escape and dry out the dish. A typical meat or vegetable lasagna does best in an oven set to 375 degrees Fahrenheit, covered with foil for about 20 minutes, followed by 20 minutes with the foil removed to allow the top to brown.

When using no-boil noodles, it is especially important that you top your lasagna with foil to ensure that your lasagna comes out of the oven cooked to perfection. No-boil noodles need the moisture of the sauce that they are cooked in to really turn out well in lasagna. By covering the lasagna until the sauce begins to boil, you are giving the noodles a chance to soften and cook before the top comes off and the sauce thickens with evaporation.

Making a classic lasagna with boiled noodles typically uses less liquid ingredients than one that has no-boil noodles. However, it is just as important to cover your dish with foil when making this type of lasagna, since boiled noodles can revert back to a hardened state when cooked at high temperatures. Seal in the tomato or bechamel flavor of your lasagna by topping it with foil until the last 20 minutes of cooking.

Making a great lasagna is an easy, yet time-consuming process. Split up the job by prepping meat and cheese mixtures up to two days in advance and storing them in the refrigerator until you are ready to assemble the lasagna. While the typical American lasagna consists of meats, tomato and cheese, don't overlook other types of traditional Italian lasagnas, like spinach lasagna or spinach prosciutto lasagna with a bechamel sauce made from butter, milk and flour.