Felix, I request sandwiches and potion (6)
I believe the answer is:
elixir
'potion' is the definition.
(elixir is a kind of potion)
'felix i request sandwiches' is the wordplay.
'sandwiches' indicates the answer is hidden within the clue (the solution is sandwiched in by the clue).
'ELIXIR' is hidden within 'felix i request'.
'and' is the link.
(Other definitions for elixir that I've seen before include "Liquid once thought to prolong life" , "Liquid remedy believed to cure all ills" , "Powerful potion" , "Liquid supposed to prolong life in olden days" , "Magical potion to prolong life" .)