Preheat oven to 400F. Saute the onion and garlic on high heat for 3 minutes in a nonstick pan. Add the mushrooms and cook until the onions are limp and the mushrooms give up their liquid. Remove them to a large bowl. Reserve the mushroom liquid in a pan to sauteĢ the other veggies. Saute the broccoli for 5 minutes and add to the mushroom bowl. Saute the peppers until they just begin to soften. Add them to the veggie bowl. Drain the tofu by wrapping in paper towels, and pressing. Break it up directly inthe towel and stir it into the veggie bowl. Add cayenne and herbs to the veggie bowl and stir. To assemble, cover the bottom of a 9×13 inch casserole with a layer of sauce. Add a layer of noodles and cover the noodles with sauce. Spread the veggie mixture over the sauced noodles. Cover with a layer of noodles and another dressing of sauce. Top with the spinach. Cover the spinach with the mashed sweet potatoes. Add another layer of sauce, the final layer of noodles, and the last topping of sauce. Cover the lasagna with thinly sliced tomatoes. Cover with foil and bake in oven for 45 minut4es. Remove foil, sprinkle with the cashews, and return to the oven for 15 minutes. Let sit 15 minutes before serving. Makes 12 servings.