Have you ever wanted one of these and not had any softened butter? (And no, we have no reason to keep margarine or the like in the house... bleh!)
I guess you could always soften some butter, use margarine or some kind of oil instead... but what if just wanted to get your grilled cheese on the road already and find a substitute for butter that would give you pretty similar results?
Mayonnaise as your grilled bread spread? At first glance, I thought this kind of strange - but upon further consideration, it's basically egg butter, right? I have to credit my university roommate for this easy solution. I would never have taken any of the liberties that she took with personal hygiene, but this grilled cheese shortcut was worth (almost) all the housekeeping digressions.
The beauty is that it always at spreading consistency, can be spread thinly on soft breads without much tearing of the bread, and is fairly neutral in taste. Of course, it doesn't have the great taste of butter but you could always add more flavour with different cheeses or...
... with a layer of bacon jam (recipe from Everyday Food magazine or via Martha Stewart). Yes, it really is a jam made of bacon. Super flavourful, seems to go well with almost everything... well I could wax philosophical for hours but maybe I'll save our discovery of bacon jam and our subsequent experimentation with it for another post.
So there you go. Grilled cheese done, throw it on a pan and grill away. The brown colour is definitely different than the beautiful golden brown you achieve with butter... but if you should ever have children screaming for grilled cheese and no time for mistakes then give mayo a try!