Cook up in bed (4)
I believe the answer is:
plot
I believe this clue is a double definition.
'cook up' is the first definition.
(I've seen this before)
'bed' is the second definition.
(I've seen this before)
'in' is the link.
(Other definitions for plot that I've seen before include "Design" , "Small piece of ground" , "Ground - plan" , "Mark position" , "Machination" .)