Yes chef is the traditional reply in professional kitchens, showing a cook has heard and understood an order. The phrase spread widely online through cooking shows, restaurant clips and short form video, where creators isolate the shout as a standalone reaction. The stretched cheffff spelling in this version reflects how users type the drawn out delivery when searching for it. It remains popular because it works outside cooking too, as a funny, instant way to agree with any boss, friend or streamer giving commands.