2 tablespoons fat-free mayonnaise
2 teaspoons Dijon mustard
4 ounces mushroom pieces
2 slices rye bread
4 ounces ham, extra lean — thinly sliced
1/2 red onion — thinly sliced
2 ounces low-fat Swiss cheese — thinly sliced
Mix together the fat-free mayonnaise and Dijon mustard. Drain the canned mushrooms well (squeeze between paper towels). Spread each slice of rye bread with the mayonnaise-mustard mixture. Set dry-side down on baking sheet. Top with mushrooms, ham, red onion, and the Swiss cheese. Rather than frying, place the “open-faced sandwich” under a preheated broiler until the cheese is melted and slightly browned.