Starchy tuber a girl served up (3)
I believe the answer is:
yam
'starchy tuber' is the definition.
(yams are starchy)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for yam that I've seen before include "Tuberous vegetable" , "Tropical tuber" , "A starchy tuber" , "Edible tuber" , "May be a sweet potato" .)