Recently I was watching a TV show with chefs competing against each other and one of the chefs made a grilled cheese sandwich. She used mayonnaise on the outside of the bread, saying that it made the bread crispier.
So I decided to do a taste test. I used my favorite jalapeño/cheddar bread from Price Chopper and good ol' processed cheese.
I spread butter on one side and I spread mayo on the other, cooking one side for the same amount of time as the opposite side
The results? No difference at all in crispiness - and no difference in taste either.
How do you make your grilled cheese sandwiches?