As fast-food places speed up their conversion to lighter oils for frying fries, upscale restaurants are eager to plop their potatoes in duck fat. Seems like an odd choice in this health-conscious climate, so it must be about the indulgent flavor and silky texture the stuff imparts to everyday spuds. And—this may sound daffy—duck fat actually checks out lower in cholesterol hazard than butter and trans fats. The chefs at Brasserie Ruhlmann Steakhouse (500 W. Superior St.; 312-494-1900), Hot Doug’s (3324 N. California Ave.; 773-279-9550), Sepia (123 N. Jefferson St.; 312-441-1920), and Sweets & Savories (1534 W. Fullerton Ave.; 773-281-6778) all go in for duck fat frites. But there’s more: Takashi (at presstime, scheduled to open late December) just upped the avian ante with goose fat frites served alongside a roasted New York strip. Goodbye foie gras (literally “fat liver”), hello goose fat (1952 N. Damen Ave.; 773-772-6170).

Photograph: Tyllie Barbosa