Feta lasagna is a baked casserole dish consisting of alternating layers of lasagna noodles, cheese, and vegetable fillings. Lasagna noodles are large, flat noodles with a long rectangular shape and ruffled edges. Lasagna is a traditional Italian dish that has become popular in many parts of the world and is usually made with an Italian curd-type cheese called ricotta. Feta cheese is a Greek curd cheese that is popular in many eastern Mediterranean cuisines and is sometimes substituted for ricotta in lasagna and other dishes.
While lasagna recipes vary widely, and almost every home cook or chef has his or her own take on this classic dish, certain aspects of any lasagna are standard. The noodles are the single most important element in any dish called lasagna, and the lasagna noodle is designed specifically for this type of casserole pasta dish. The noodles are very large, flat sheets of dried pasta, often 8 inches (20 cm) long and 2 or 3 inches (5 to 7.5 cm) wide with edges that are curled or ruffled. Size may vary somewhat depending on the brand. The noodles must usually be cooked before assembling the lasagna, but some types are available that allow this step to be skipped.
The filling is the other main component of a lasagna dish. A traditional lasagna is constructed by alternating layers of lasagna noodles with tomato sauce and cheese after which the lasagna is baked. The sauce may have meat or vegetables in it. Many variations are possible, including white sauces such as alfredo, all kinds of vegetables and mushrooms, and a variety of meats such as beef, sausage, chicken, or even seafood. A typical lasagna is made with ricotta cheese, often mixed with egg to give the cooked casserole a firmer texture after baking.
Other cheeses such as mozzarella and Parmesan are also common. A feta lasagna dish uses feta cheese instead of the ricotta. It may or may not be mixed with egg before cooking, and other cheeses may or may not be used, according to preference. Many feta lasagna variations are more in line with Greek cuisine than Italian styles and often contain spinach, chicken, olives, and fresh tomatoes but omit the tomato sauce found in many lasagnas. Of course, this is not a hard and fast rule and almost any combination of traditional or personal favorite lasagna ingredients can be found in a feta lasagna.