Rasher being without a taxi - reverse! (5)
I believe the answer is:
bacon
'rasher' is the definition.
(I've seen this before)
'without a taxi reverse' is the wordplay.
'without' becomes 'no'.
'a taxi' becomes 'cab' ('cab' can be a synonym of 'taxi').
'reverse' is a reversal indicator.
'no'+'cab'='nocab'
'nocab' reversed gives 'BACON'.
'being' acts as a link.
(Other definitions for bacon that I've seen before include "Irish-born painter" , "modern artist" , "Cured back or side of pork" , "Man killed by chicken, some say" , "Meat (that's brought home?)" .)