Hamburger or sandwich buns which have bits of onions baked into the bread.
They are delicious enough to eat all by themselves -- without any meat, cheese, sauce, or anything else inside 'em -- and they are guaranteed to impress everyone at your next cookout. The mere smell of a freshly-opened bag of onion buns is enough to kill any diet.
They're sometimes hard to come by, since they are usually sold only in the summer and since not all bakeries make them. But if you can find 'em, pick up a few packages and start planning your week around your sandwiches...