Grilled cheese sandwich with tomato-onion jam and arugula

slices from a crusty sourdough bread – don't buy the pre-sliced stuff on the shelves. Buy the kind in the bakery.

thin slices (or so) from a block of sharp cheddar cheese – don't use "cheese product"; it should really be cheese. (They try to trick you with their low prices!) ;)

spoonfuls of tomato-onion jam.

small handful of arugula (enough to cover out all the cheese so that very little yellow would peek through if you mounded the arugula)

room temperature butter

salt, if your cheese isn't salty enough