From Longman Dictionary of Contemporary Englishbe cooking (with gas)be cooking (with gas)EFFICIENT spoken used to say that someone is doing something very well The band’s really cooking tonight. → cook
Examples from the Corpus
be cooking (with gas)• The air was rippling with heat above the goats, as if they were cooking.• While the rice is cooking, add the saffron to the stock and allow to stand. 4.• While the Quorn mixture is cooking, cook the rice according to the instructions.• Laundry flew from the flagpoles; windows were broken or boarded-up; there were cooking fires in the roads.• Soon I saw a small hut where an old man was cooking his breakfast over a fire.• While parsnips are cooking, in a small skillet, saute onion and saffron in butter until soft but not browned.• Once in a while, think about why you are cooking, serving and eating together as a family.• The East Village was cooking then. 