Olive Garden Florentine Lasagna

1 pound fresh spinach
1 pound fresh mushrooms, chopped coarsely
1 cup onion, chopped
1 clove garlic, minced
2 tablespoons olive oil
3 cups ricotta cheese
1 2/3 cups Parmesan cheese, divided
1 egg
1/2 teaspoon salt
1/2 teaspoon black pepper
3/4 teaspoon dried basil
3/4 teaspoon dried oregano
16 lasagna noodles
4 1/2 cups mozzarella cheese, shredded
Marinara sauce or tomato-cream sauce as desired
Extra Parmesan cheese

Steam spinach until tender; press out excess moisture and chop coarsely.

Chop mushrooms and onions and mince garlic over medium-high heat until onions are tender; drain excess liquid and cool.

Mix ricotta cheese, 2/3 cup Parmesan, egg, salt, pepper, basil and oregano in large bowl. Add cooled spinach and mushroom-onion mixture and mix on low speed until just blended.

Cook lasagna according to package directions; rinse under cool water and drain thoroughly.

Place four lasagna strips in bottom of lightly oiled 9 x 13-inch pan, overlapping slightly. Top with 2 cups of spinach filling. Sprinkle with 1 1/2 cups shredded cheese and 1/3 cup Parmesan. Repeat layering two more times and top with remaining four lasagna strips. Spread 1 cup of marinara or tomato-cream sauce over top and cover tightly with foil.

Preheat oven to 350 degrees F and bake, covered, for 1 hour. Remove from oven and keep warm at least 30 minutes before cutting. Top with extra Parmesan cheese. (Can be refrigerated a day in advance of baking if desired.)