These Stuffed Portobello Mushrooms with Roasted Tomatoes, Peppers, and Feta Cheese make a great vegetarian entrée or a delicious appetizer. Portobello mushrooms are meaty and have a rich flavor. Make the Oven-Roasted Tomatoes recipe in advance. You can also roast some red peppers,  but I often buy my roasted red peppers in a jar to