Step 1Spread the jam evenly on both pieces of bread.
Step 2Crumble the cheese or cut it into small chunks, then distribute it over one slice of bread, taking care not to get it too close to the edge. Press the other slice of bread on top so that the cheese adheres to the jam.
Step 3It you have a griddle for making grilled cheese sandwiches, use that according to its instructions. Otherwise, gently melt the butter in a skillet and then, before it browns, place the sandwich carefully in the middle. Immediately press down on the sandwich with a metal spatula until the bread is somewhat browned and the cheese starts to melt.
Step 4Lift the sandwich carefully, swirl the butter in the pan and then, using your fingertips for support against the bread and the spatula, flip the sandwich over and then slide it back into the pan. Press down with the spatula until the bottom side of the bread has toasted (but not burned) and the cheese has melted. If the cheese has barely melted, place the sandwich on a baking sheet in a 350-degree oven for 5 to 8 minutes. It tastes best when the cheese is oozing. Serve immediately.