Believe it or not, bed sheets are a great addition to food photography. My personal favorite use for them is to create a faux “breakfast in bed” look in a photo.
You can also use them as a tablecloth in a pinch, or even as a window filter for light if you don’t have a diffuser. They can even make lovely backdrops if you drape them over a chair or large board in the background.
Many beginner food photographers start with bed sheets for all of these purposes. They are large enough for any surface, cheap, and you probably already have them.