Butter all 4 slices of bread on one side only. Sprinkle chopped herbs on top of the buttered side of each slice.
Turn two slices of the buttered bread over, then top with half of the shredded cheese, 3 slices each of Canadian bacon, and 2 slices each of pineapple rings. Top with the remaining cheese and the other two slices of bread, buttered-side-up.
Cook each sandwich on a griddle or frying pan over medium heat until golden brown and toasted on both sides (about 4-5 minutes). Toward the end of cooking, turn heat to low and cover pan for 1-2 minutes or until the cheese is melted.