Mixer left in drinking session (7)
I believe the answer is:
blender
'mixer' is the definition.
(blender is a kind of mixer)
'left in drinking session' is the wordplay.
I cannot really understand how this works, but
'left' could be 'l' (common abbreviation) and 'l' is found in the answer.
The remaining letters 'bender' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for blender that I've seen before include "Kitchen appliance" , "Liquidising device" , "Kitchen utensil" , "Kitchen liquidiser" , "kitchen equipment" .)