Tip for grilling sandwiches: butter the pan, not the bread.
When you butter the bread, at least one side always ends up soggy. Sometimes both sides do. But, if you start with a hot pan, and smear butter just in the spot where the bread will sit (or as close as you can manage when eyeballing it), then the bread only absorbs a little of the grease, giving you a perfectly crisp, grilled surface.
Flipping the sandwich can be tricky. If the pan is big enough, butter a spot to flip it to right before flipping. If the pan is too small, have the butter right there ready to go, lift the sandwich with one hand, butter the pan with the other, then flip the sandwich into the freshly-prepared spot.
My grandfather has been in the restaurant business, either as owner/chef or just head chef, for more than 60 years. He told me it wasn’t possible to make a grilled cheese sandwich without one side ending up soggy. I hate soggy bread enough that I just had to fix that. He said it was the best grilled cheese he’d ever had, and he is NOT one to hand out empty compliments!
If you absolutely must butter the bread, keep the top piece away from heat until you’re ready to flip it, or else grill both pieces separately and assemble the sandwich after they’ve grilled. The key is not to let the butter melt into the bread until said bread is touching the hot surface.
Thx for the pro cheffy tips.