Grilled Club Sandwich
Preheat the oven broiler. Grill the bread slices under the oven broiler on both sides, watching carefully. While still lukewarm, spread each slice with 1 teaspoon of mayonnaise. Top 4 slices of bread with 1 slice of cheddar, 1/2 slice of ham and a slice of Emmentaler. Sprinkle with ground pepper.
Place a second slice of bread with the mayonnaise side up on each stack. Top again with cheddar, sorrel, tomato slices and Emmentaler. Season with salt and pepper. Top with the third slice of bread with mayonnaise side down. Cut the sandwiches diagonally. Secure with wooden skewers and serve immediately.