This cheese and sausage quiche contains eggs, cooked sausage, and two varieties of cheese. Not only are eggs used in the filling mixture, but they are also sliced hard-boiled eggs layered in the quiche. You get a double dose of protein from the eggs along with sausage and cheese for flavor and texture. Feel free to use different cheeses if you'd like. Monterey jack cheese or gruyere are good options or use a cheddar jack blend. Vegetables can be added to the quiche as well. Saut some finely chopped onions or shallots, sliced mushrooms, or diced bell pepper. Use spicy or mild pork sausage or italian sausage in this quiche, or make it with turkey sausage.