Fruit: piece of bread almost sandwiching it (6)
I believe the answer is:
citrus
'fruit' is the definition.
(I know that citrus is a type of edible fruit)
'piece of bread almost sandwiching it' is the wordplay.
'piece of bread' becomes 'crust' (bread has a crust).
'almost' means to remove the last letter (most of the word but not all of it).
'sandwiching' means one lot of letters goes inside another (to sandwich can mean to contain or block in).
'crust' with its last letter taken off is 'crus'.
'crus' placed around 'it' is 'CITRUS'.
(Other definitions for citrus that I've seen before include "Fruit such orange, lemon etc." , "it bears fruit" , "Lemons, limes, oranges etc." , "source of fruit" , "Rustic (anag) - type of fruit" .)