Spread mayonnaise on half the slices of bread and the mustard on the other half. Then toast the bread lightly.
Slice the tomatoes into 8 thick slices and sprinkle with salt and pepper.
To assemble each sandwich, layer some of the mixed deli slices, 2-3 lettuce leaves, 2 slices of tomato, 2 slices of swiss, 2 slices of sharp cheddar cheese, a few slices of red onion and some of the alfalfa sprouts. Enjoy!