Steps
1. Spread butter on one side of each bread slice.
2. Place one slice of cheese on the non-buttered side of one bread slice.
3. Spread ketchup and mayonnaise on top of the cheese.
4. Top with the remaining slice of cheese.
5. Place the other bread slice on top, buttered side facing outwards.
6. Heat a pan over medium heat.
7. Place the sandwich in the pan and cook for 2-3 minutes on each side, until the bread is golden and the cheese has melted.
8. Remove from the pan and let it cool slightly before serving.