Pasta to supply a boost, mainly (8)
I believe the answer is:
rigatoni
'pasta' is the definition.
(rigatoni is a kind of pasta)
'supply a boost mainly' is the wordplay.
'supply' becomes 'rig' (to rig a boat is to provide it with sails).
'boost' becomes 'tonic' (tonic can mean a stimulant or booster).
'mainly' means to remove the last letter.
'tonic' with its last letter taken away is 'toni'.
'rig'+'a'+'toni'='RIGATONI'
'to' is the link.
(Other definitions for rigatoni that I've seen before include "Pasta; at origin (anag.)" , "Foodstuff" , "Short fluted tubes of pasta" , "Pasta dish" , "Short, ribbed, tubular pasta" .)