Make a delicious alternative to the usual barbecue burger. These Grilled Portobello Sandwiches get added flavor from grilled onions and peppers, all smothered in tomato sauce and provolone cheese. Ingredients 1 lb. Portobello mushrooms, sliced 1 onion, sliced thin 1 green bell pepper, Julienned 1 red bell pepper, Julienned 1/4 cup extra virgin olive oil […]