Grilled Swiss, Tomato and Avocado Sandwiches are amazing. These delicious Grilled Cheese Sandwiches use Swiss cheese instead of cheddar. The addition of tomatoes and avocados make this sandwich utterly mouthwatering and the ultimate in comfort food. This is a wonderful meal to serve on weekends when you have busy sports schedules crowding out time in the kitchen. Good for Meatless Mondays too.