This isn't classic Quiche Lorraine but it is my "go to" never fail recipe. You will never have an underdone center or a watery quiche with this recipe. You can substitute cooked ham with cheddar, cooked sausage with cheddar. Try chorizo and pepper jack cheese or chopped cooked shrimp with a 1/2 t of Old Bay Seasoning. The variation possibilities are up to you. If I have a bit more time I use a packaged roll out crust. The basic "liquid" is the key. Feel free to add veggies but not veggies that will give off too much liquid while baking in the quiche.Mushrooms sauteed in butter are a wonderful addition.