Preheat oven if your full recipe requires baking; otherwise prepare fillings and have all components ready.
Lightly oil the bottom of a baking dish with extra-virgin olive oil to prevent sticking.
Spread a thin, even layer of tomato sauce over the bottom of the dish.
Place a single layer of lasagna noodles over the sauce.
Spread half of the seasoned ricotta over the noodles, then add half of your desired fillings and a little more tomato sauce.
Add another layer of noodles, then spread the remaining ricotta, remaining fillings, and more sauce.
Top with a final layer of noodles, spread the remaining sauce evenly over the top, and sprinkle with shredded mozzarella and Parmesan.
Bake according to your full lasagna recipe instructions until heated through and cheese is melted; see the full vegetable lasagna recipe for exact baking time and temperature.