Mushroom and Onion Lasagna

1 package lasagna noodles
10 ounce package button mushrooms or a mix of several types of mushrooms
2 large Spanish onions, sliced lengthwise
1 pound mozzarella cheese (part skim), grated
1 pound Swiss cheese, grated
1 or 2 pounds  ricotta cheese
Grated fresh Parmesan cheese
Salt and pepper to taste
olive oil

Boil lasagna noodles according to package directions (you won't need the entire package).
Oil a 9x13 casserole dish.
Saute mushrooms in a tablespoon or two of olive oil. Make sure that all of the liquid evaporates. Season with salt and pepper to taste.
Saute onions until golden brown. Season with salt and pepper to taste.
Mix ricotta cheese with salt and pepper to taste.
Grate both mozzarella  and Swiss cheese and mix together.
Layer the bottom of the casserole dish with lasagna noodles. Cover with ricotta cheese. Spread a layer of mixed Swiss and mozzarella. Spread a layer of mushrooms and then a layer of onions.
Repeat with lasagna noodles, cheeses, mushrooms and onions.
Top with a layer of noodles. Spread a final layer of Swiss and mozzarella cheeses. Top with a sprinkling of Parmesan cheese.
Bake in a 350 degree oven for 1 hour. Cover with aluminum foil for the first half hour. If the top isn't brown at the end of an hour, increase the heat to 375 and bake until golden.