Cook the noodles. Bring a large pot of salted water to a boil and cook lasagna noodles until al dente (about 10 minutes). Drain and rinse with cold water to prevent sticking.
Sauté the veggies. In a large skillet, heat oil over medium heat. Add mushrooms, bell pepper, onion, and garlic. Sauté until softened, about 5 minutes.
Make the sauce. Stir in pasta sauce and dried basil. Bring to a gentle boil, then reduce heat and let simmer for 15 minutes.
Prepare the cheese mixture. In a medium bowl, mix ricotta cheese, 2 cups of mozzarella, and eggs until well combined.
Preheat oven. Set oven to 350°F and grease a 9x13-inch baking dish.
Assemble the lasagna. Spread 1 cup of pasta sauce in the bottom of the dish. Layer half the noodles, half the ricotta mixture, half the sauce, and half the Parmesan. Repeat the layers and finish with the remaining 2 cups of mozzarella.
Bake. Cover loosely with foil and bake for 40 minutes. Remove foil for the last 10 minutes to get a golden, bubbly top.
Let it rest. Remove from the oven and let stand for 15 minutes before slicing. Enjoy!