Preheat the oven to 350 degrees F. Bring a large pot of salted water to a boil. Make the sauce: Heat the olive oil in a medium saucepan over medium heat. Add the carrot, zucchini, onion and celery and saute until soft but not brown, 5 minutes. Add the garlic and cook for 5 minutes, stirring occasionally. Add the basil, oregano, tomato paste, crushed tomatoes and 2 cups water. Bring to a boil, then reduce the heat and simmer for 15 minutes. Season with salt and pepper.

Meanwhile, prepare the shells: Add the pasta to the boiling water and cook for 8 minutes; drain. Mix the tofu, spinach, cottage cheese, parmesan, 1/2 cup mozzarella, the egg and garlic in a medium bowl and season with salt and pepper.

Mist a 9-by-13-inch baking dish with cooking spray. Spread about 1 cup of the sauce in the dish. Stuff the cheese mixture into the shells and place in the baking dish, open-side up. Pour the remaining sauce over the shells. Cover tightly with foil and bake for 30 minutes. Uncover, sprinkle with the remaining 1 cup mozzarella and bake for 15 minutes. Let cool slightly before serving.

Photograph by Ngoc Minh Ngo