Brownies team tucking into food (6)
I believe the answer is:
pixies
'brownies' is the definition.
('pixy' can be a synonym of 'brownie')
'team tucking into food' is the wordplay.
'team' becomes 'xi' (eleven, a football team).
'tucking into' means one lot of letters goes inside another.
'food' becomes 'pies' (I've seen this before).
'xi' inserted within 'pies' is 'PIXIES'.
(Other definitions for pixies that I've seen before include "Elves, imps" , "Mischievous fairies" , "Little (mischievous) people" , "small fairies in children's tales" , "Small supernatural beings in fairy tales" .)