Mop Up Meaning

(transitive) To clear the leftovers of a dish, in order to eat them.

Example: To clean up with a mop; especially to clean up a spill or mess.
  Please mop up the spilled milk.
April 19 2002, Scott Tobias, AV Club Fightville[1]
  And though Fightville, an MMA documentary from the directors of the fine Iraq War doc Gunner Palace, presents it more than fairly, the sight of a makeshift ring getting constructed on a Louisiana rodeo ground does little to shake the label. Nor do the shots of ringside assistants with spray bottles and rags, mopping up the blood between rounds
  After they argued, it fell to me to talk to her and try to mop up.
2011 March 2, Andy Campbell, “Celtic 1 - 0 Rangers”[2], BBC:
  Diouf rounded Zaluska near the byeline and crossed but Daniel Majstorovic headed away and Celtic eventually mopped up the danger.
2003, Jeff Call, Rolling With the Tide Page 112
  He mopped up the sauce with the bread and scarfed it down like he had been raised by wolves.