Don't be intimidated by someone who knows their craft, many of us were chefs in a former life and we know what chef's like. A bigger chef's knife like a 210mm, 240mm or even 270mm is the perfect first-knife for the professional, or aspiring professional. Better yet, pair a chef's knife with a smaller petty, and you've got the start of a serious knife set!
If they're already well-equipped, then they're going to need a solid knife-roll to store their gear in, and a set of sharpening stones to keep a keen edge on their tools. If you only need a few stocking stuffers, no chef can leave home without a Kuhn paring knife, a silicone spatula, and a decent thermometer.