Power Potato (3.5e Equipment)
From D&D Wiki
This magical tuber is big enough to serve two medium size creatures (or one large creature, or 4 small or smaller creatures). It is not uncommon for this potato to be chopped up into stews, thick soups or other dishes. The magic of the potato remains despite being chopped and cooked. The eater of this potato is provided with nourishment enough to last for an entire day as well as provide a +4 resistance bonus on all saves against fatigue for 24 hours. A single potato costs 4 gold pieces. It looks much like any other potato except that upon inspection, with detect magic, it glows with a faint aura of abjuration magic.