From Longman Dictionary of Contemporary Englishcook something ↔ up phrasal verb1 DFCCOOKto prepare food, especially quickly Every night he cooked up a big casserole.2 informalINVENT to invent an excuse, reason, plan etc, especially one that is slightly dishonest or unlikely to work the plan that Graham and Dempster had cooked up → cook→ See Verb table
Examples from the Corpus
cook up• He hadn't eaten all day, so he opened one of them and cooked it up.• Idly I wondered why he insisted on them being cooked sunny side up.• Instead, Miss Arabel wrote, in her neat, tidy script, and Mr Surtees Cook.• The cooks were up at 0500 hours, preparing the usual early breakfast for men condemned to hard work.• Yes, of course he did, probably thought she and Donal had cooked it up between them.• The cook stood up on the forward side, so that the shed protected him when there was a favourable wind.• The kitchen with a small staff cooked or warmed up the men's food free of charge.• We then add a blend of other unusual rices to it and cook them up together. 