The grilled cheese sandwich is one of the simplest and most delicious creations that mankind has created. This is one of the most perfect examples of a completed product being vastly superior to the sum of its ingredients. At its most basic level, a grilled cheese is simply cheese placed between bread, and then heated. In general, the sandwich is complete when the exterior crust of the bread is a golden brown, and the interior is a gooey, melted consistency. There are many decisions to make about the specifics of how one achieves this goal, notably what form of oil to use to lubricate the heat source and the bread, what sort of cheese to use, whether to cook both sides of each side of bread, and of course, whether to add a delightful slice of meat in the middle.
This section is titled Melts for a reason, which is because if you place a primary ingredient other than cheese or a cheese modifier into a sandwich, it stops to be a "Grilled Cheese" entirely. The addition of a delicious piece of bacon, arugula, or walnuts transforms your sandwich into a Melt.