Hastily seize the sauce (5,2)
I believe the answer is:
catch up
'sauce' is the definition.
(I've seen this before)
'hastily seize' is the wordplay.
I cannot really see how this works, but
'seize' could be 'catch' (catching is a kind of seizing) and 'catch' is present in the answer.
The remaining letters 'up' 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).
'the' is the link.
Can you help me to learn more?
(Other definitions for catch up that I've seen before include "Draw level" , "Backward student must try to do this" , "Sauce" , "Prepare to overtake" , "Lag no longer" .)