Burnt outside, cold inside, means the pan is too hot.
Steps:
1. warm up pan, just below a sizzle
2. If you want something fancy, sautee that now, then slide onto a plate for later (onions, mushroom, water cress, etc.)
3. Get cheese ready
4. Put in two slices of bread.., pan needs to be hot enough that the bread doesn't soak up too much butter, cold enough that the bread turns brown, not black
5. Once the bottoms of the bread are brown, flip one over, put on cheese, put second bread slice on the cheese mound with toasted side to cheese
6. Once the bottom is toasted flip very carefully so last side can toast.
7. After it has flipped carefully open sandwich and slide "fancy stuff" ontop of the unmelted cheese. (So bottom bread slice starting to toast, some unmelted cheese that is starting to melt, the "fancy stuff" , then already melted cheese, top slice of bread already toasted both sides)
8. Once the bottom slice is brown on bottom, slide it out of the pan, add any cold goodies (like some sprouts), and eat.