"Here we take the elements of a vegetarian lasagna filling—ricotta, spinach and Parmesan cheese—and nestle them into roasted portobello mushroom caps. The recipe works best with very large portobello caps. . . Serve with a tossed salad and a whole-wheat dinner roll or spaghetti tossed with marinara sauce." Note: After making this dish, I have changed the recipe slightly from the original (increased it to 6 mushrooms from 4, added garlic and chives, then mozarella on top instead of parmesan. If you like spicy stuff, I would recommend adding a few crushed red pepper flakes to the marinara sauce. Recipe from Eating Well.