Sushi! Sushi is pretty broad as far as varieties go but honestly I'd probably eat any one particular roll that I like whether hot or cold as long as I like the roll already (the ingredients).
This one's very specific - fluffernutter sandwich. If you grew up with them, I'm guessing you had them cold (room temp, maybe a little cool from an ice pack in the lunch bag?), and having one now takes me right back to my childhood. But my favorite way to eat them is to grill them. Everything gets melty and gooey. It's the ultimate comfort food, especially on a cold day.
This is pretty original coz it could be hot coffee or iced coffee. I honestly like both but on a hot day I would take an iced coffee and on a cold day I take a usual coffee. I'm not sure it counts coz coffee and iced coffee are quite different things instead of like cold or hot lasagna. But pizza is not that bad cold, but the best when it is hot pizza.