Preheat the oven to 400°F. Line a baking sheet with parchment paper.
Place the eggplant, zucchini, red pepper, and onion on the prepared baking sheet. Drizzle with olive oil and season with salt and pepper. Roast for 25 minutes or until vegetables are tender and lightly browned.
In a large skillet over medium heat, sauté garlic in 1 tablespoon of olive oil until fragrant, about 30 seconds. Add crushed tomatoes, tomato paste, basil, oregano, salt, and pepper, stirring until combined.
Reduce heat to low and let the sauce simmer for 20 minutes, stirring occasionally.
Cook the lasagna noodles according to the instructions on the package, then drain and set aside.
Reduce the oven temperature to 375°F.
Spread a thin layer of tomato sauce in the bottom of a 9x13 inch baking dish. Place a layer of lasagna noodles on top of the sauce, followed by a layer of roasted vegetables.
Repeat these layers until you have used up all the vegetables and noodles, ending with a layer of noodles.
Spread the vegan ricotta cheese (if using) over the top layer of noodles, then sprinkle the vegan mozzarella cheese on top.
Cover the baking dish with foil and bake for 20 minutes
Remove the foil and continue baking for an additional 10 minutes or until the cheese is melted.
Let the lasagna cool for a few minutes before slicing and serving.