Spread the peanut butter one slice of bread and the jelly (or jam) on the other slice.
Sprinkle the shredded cheese over the jelly side, close the sandwich with the peanut butter side.
Lightly butter one side of the bread or spray it with oil to create a crispy and golden crust.
Heat a medium cast iron or non-stick pan over medium heat. Once hot, place the sandwich buttered-side down, reduce the heat to medium-low, and grill the sandwich for about 2 minutes.
Once the bottom side is nice and golden brown, spread butter on the top side (or spray it), flip it, and grill it for an additional 2 minutes, until the cheese has melted and both sides are nicely golden.
Remove from the pan and enjoy immediately.
Pack this sandwich for school by allowing it to cool down to room temperature completely, about 10 minutes, before placing it inside a lunch container.