On hectic nights, make sandwiches to eat on the go – they’re good either hot or at room temperature. Instead of hamburgers, grill or roast meaty Portabella mushrooms and serve them as you would the higher-cholesterol beef. To store Portabella mushrooms, remove from any packaging and refrigerate in a paper bag for seven to ten days.
Coat the mushrooms with cooking spray. Mix the vinaigrette ingredients and paint the mushrooms on both sides. Marinate for 15 minutes.
Coat the marinated mushrooms and the onion slices with cooking spray. Roast them in the oven until cooked through, about 5 minutes.
Coat the bread with the cooking spray and toast in a toaster oven. Place a slice of cheese on four pieces of toast. Top with mushroom, slices of onion, red pepper, tomato and a basil leaf.
Combine the mayonnaise, vinegar and mustard. Paint each top slice of bread with a quarter of the Balsamic Mayonnaise. Assemble the sandwiches and serve immediately.
Dietitian's Note: A 3-ounce Portabello mushroom has only 27 calories, 0 grams of fat, 1 gram of fiber and lots of flavor. Compare that to a 3-ounce serving of ground beef (10% lean), which has 180 calories, 9 grams of fat, 4 grams of saturated fat and 0 grams of fiber.