Dupes on cooking supply missions tend to drop items while traversing ladders. I've observed a Dupe in an endless loop, carrying meat up a ladder, dropping it after moving a few tiles, going down to pick it up, climbing the ladder, and then dropping it again. There's a delay between the Dupe dropping the food and aborting the errand. For a second or two the Dupe is still executing a cooking supply errand while carrying nothing.
Save / reload fixes the problem temporarily, so it's difficult to provide a save file demonstrating the problem. It's quite common, though.
Not really reproducible on demand. Generally speaking it happens often enough that a few minutes play will produce it, if there's a long ladder between the food source and the grill.