- 4 portobello mushroom caps, gills removed if desired
- Cooking spray
- ¼ teaspoon ground pepper
- 2 tablespoons mayonnaise
- 1 tablespoon ketchup
- 1 tablespoon sweet pickle relish
- 4 teaspoons steak sauce
- 4 slices American cheese
- 4 whole-wheat buns, toasted if desired
- 1 cup shredded iceberg lettuce
- 4 large tomato slices
- Thinly sliced red onion & pickles (optional)
- 1Preheat grill to medium-high.
- 2Coat mushrooms with cooking spray and sprinkle with pepper. Grill, turning occasionally, until tender, 10 to 12 minutes total.
- 3Meanwhile, mix mayonnaise, ketchup and relish in a small bowl.
- 4Transfer the mushrooms to a plate and pat dry with paper towels. Brush with steak sauce and top the gill side of each mushroom with a slice of cheese. Return the mushrooms to the grill and cook until the cheese is just melted, about 1 minute more. Serve on buns with the sauce, lettuce, tomatoes and onion and pickles, if desired.