Ms Le Pen covers Bill in spicy sauce (8)
I believe the answer is:
marinade
'spicy sauce' is the definition.
(I've seen this before)
'ms le pen covers bill' is the wordplay.
I cannot quite understand how this works, but
'bill' could be 'ad' (advertisement stuck on wall) and 'ad' is located in the answer.
'le pen' could be 'marine' (Marine Le Pen) and 'marine' is found in the remaining letters.
This accounts for all the letters.
This explanation may well be incorrect...
'in' acts as a link.
Can you help me to learn more?
(Other definitions for marinade that I've seen before include "Soak in a mixture before cooking" , "get saturated" , "Type of star system" , "Liquid for soaking food before cooking" , "Steep in flavourings" .)