If a zombie dies while on fire and drops a potato, it isn't cooked.
Linked issues
Comments 2
This was actually fixed in 1.17, see MC-199065.
MC-41576
Flame zombies dont make cooked potatoes
Resolved
Works As Intended
0
Zombies were intended as a source of potatoes if you could not locate a village. All dropped items are not cooked.
At the best this is a feature request.
For feature suggestions or changes please do this on Minecraft Suggestions on Reddit.