Preheat oven to 375º. In a large pot of salted boiling water, cook pasta according to package directions until al dente, less 2 minutes. Drain and drizzle a bit of olive oil to prevent noodles from sticking together.
Meanwhile, in a large pot over medium-high heat, warm 1 teaspoon olive oil. Dice veggies into small cubes, saute until barely soft then add garlic and oregano and stir for 1 minute. Season with salt and pepper, then add marinara and stir until warmed through. Combine ricotta, half of the Parmesan, and parsley in a large mixing bowl and set aside.
In a large casserole dish, spread a thin layer of veggie sauce, a single layer of lasagna noodles, a single layer of mozzarella, and a layer of ricotta mixture, then repeat layers. Top last layer of noodles with veggies sauce, Parmesan, and mozzarella.
Cover with foil and bake for 30-45 minutes, until cooked through and bubbly. Remove foil to brown top layer of cheese. Garnish with parsley and serve.