Preheat oven to 375°. Lightly spray a 9-by-13-inch baking dish with nonstick spray; set aside.

Cook pasta in salted boiling water for 8 minutes. Drain; return pasta to pot.

Heat olive oil in a large nonstick skillet. Add mushrooms and onion. Cook for 5 minutes over medium heat, stirring occasionally. Add sliced sausage and Italian seasoning; cook for 4 to 5 minutes or until mushrooms are softened and sausage is cooked through (165°). Add mushroom mixture and pasta sauce to pasta in pot. Gently stir to combine.

Whisk together beaten eggs and ricotta until combined. Stir in 1 cup Italian cheese and ¼ cup Parmesan cheese.

Spread half of the pasta mixture in the prepared baking dish. Top with the ricotta mixture, spreading evenly on pasta layer. Cover ricotta layer with remaining pasta mixture. Tightly cover baking dish with foil.

Bake for 20 minutes. Remove foil; sprinkle with remaining 1 cup Italian cheese. Bake, uncovered, for 10 to 15 minutes more or until heated through and cheese is melted. Let stand for 5 minutes before serving. Garnish with basil, if desired. Serve with additional Parmesan cheese.