Grilled Cheese

I don't go to Red Robin very often, but a few years ago I took my kids and ordered a grilled cheese sandwich for myself. Let me tell you, that was a small piece of heaven. They removed it from the menu quite a while ago and I miss it. Is that just me, or does anybody else remember that sandwich fondly?

I have heard rumblings about people putting mayonnaise on the outside of their bread used for grilled cheese sandwiches and it being the best thing ever. I haven't had the guts to try it myself. Has anybody heard the rumors and/or done this? How did it turn out?