Entertain lavishly with flipping English beer (6)
I believe the answer is:
regale
'entertain lavishly' is the definition.
(I've seen this before)
'flipping english beer' is the wordplay.
'flipping' says the letters should be written in reverse.
'english' becomes 'E' (abbreviation).
'beer' becomes 'lager' (type of beer).
'e'+'lager'='elager'
'elager' backwards is 'REGALE'.
'with' is the link.
(Other definitions for regale that I've seen before include "Feed or entertain well" , "Entertain with stories" , "Fete" , "Amuse with stories" , "Feast, give pleasure to" .)