Formal/General:
* Petite pomme de terre: This is the most literal and common translation.
* Petite patate: This is a more informal way to say "little potato," but still widely understood.
Informal/Cute:
* Petite patate douce: This translates to "little sweet potato," which is a cute way to refer to a small potato, especially if you're talking to a child.
For a specific type of small potato:
* Pomme de terre nouvelle: This refers to a "new potato," which is typically small and has thin skin.
Remember, the best way to choose the right phrase depends on the specific situation and your intended meaning.