We have something in this part of Illinois called a horseshoe sandwich. The gold standard is a hamburger served on toast and smothered in fries and cheese sauce, but there are all kinds of variations. You can put any kind of protein in place of the hamburger; I have seen everything from fish to italian beef, cold cuts, and even fried eggs. Any kind of potato can be used in place of the fries; tater tots, waffle fries, homemade chips, etc, and the true mark of a good horseshoe is how good the cheese sauce is. Some places make it spicy, some add beer, some use fancy cheeses. Some places even add a little bit of chili or another flavored sauce on top. A true indulgence, but amazing to eat.
My favorite regular sandwich is just a lettuce sandwich, when fresh lettuce comes in during the spring. A couple slices of toast or grainy german pumpernickel, spread thin with butter. Add a handful of lettuce fresh from the garden, a sprinkle of salt, and occasionally a smear of mustard. Best treat ever after a long winter.