You may substitute chickpeas for lentils.
(If Portobello is quite thick, cut out a bowl of mushroom "meat" and chop and add to mixture) Preheat oven to 400°F. Spray large fry pan with cooking spray. Add mushrooms, onion, celery, zucchini, peppers and garlic. Cook until tender. While chopped veggies are cooking, put Portobello cap into cooking-oil sprayed pan. Place in the oven to start the cooking process. When veggies are tender, add the chopped tomato and remove from heat. In medium bowl, combine, vegetable mixture, lentils, half (2 tablespoons) of the mozzarella cheese and egg substitute. Remove cap from oven. Fill cap with filling. Mixture will overflow. Return to oven. Cook for approximately 15 minutes. Remove from oven and top with remaining cheese. Cook an additional 5 minutes until cheese is melted and bubbly brown. Remove from oven and drizzle with the extra virgin olive oil. Serve with raspberries for dessert. **Note: If you're not a lentil lover, as their taste takes some getting used to, you could easily substitute 1/4 chickpeas mashed. As well as completing your carb requirement, it acts as a binding agent in place of traditional bread crumbs, which are an unfavorable carb.