Start making jokes -- or omelettes? (3,8)

I believe the answer is:

get cracking

I'm a little stuck... Click here to teach me more about this clue!

'start' is the definition.
(to get cracking is to start or begin)

I cannot understand how the rest of the clue works.

(Other definitions for get cracking that I've seen before include "Prepare to break from shell" , "Start something at once" , "Act quickly and decisively" , "Bestir oneself" , "start flying" .)

I've seen this clue in The Telegraph.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.