Bring a large pot of lightly salted water to a boil. Add the lasagna noodles and olive oil; cook until al dente, 8 to 10 minutes; drain.
Cook the ground beef and sausage in a large pot over medium heat; drain. Stir in the mushrooms, garlic salt, oregano, thyme, basil, and tomato sauce. Season with salt and pepper; simmer 30 minutes.
Meanwhile, mix together the ricotta cheese, eggs, and Parmesan cheese in a bowl.
Ladle enough of the meat sauce into a 9x13 inch baking dish to cover the bottom in a thin layer. Form a layer atop the sauce with 3 of the lasagna noodles. Spread about 1/4 of the ricotta cheese mixture over the noodles. Sprinkle about 1/3 of the mozzarella cheese over the ricotta cheese mixture and then ladle about 1/3 of the meat sauce over the mozzarella cheese. Repeat layering twice more, topping with the remaining 1/4 pound of mozzarella cheese.
Bake in preheated oven 90 minutes. Allow to sit 10 to 15 minutes before serving.