I got this recipe from my sister. It's the only one I use.
one box lasagna noodles
1 lb hamburger
15 oz ricotta cheese
1 lb shredded mozzarella cheese
1 egg
black pepper
15 oz jar spaghetti sauce
Brown hamburger, drain and add sauce. Simmer on low. Mix egg and Ricotta cheese. Cook noodles until al dente. In a 9 x 13 pan layer noodles, cheese mixture, sauce, and mozzarella cheese. Use the black pepper to your taste. Repeat layers until you get to the top of the pan. Bake at 350" for about 40 minutes. Let cool just a bit before cutting.