Jean-Georges Vongerichten uses homemade syrups to add concentrated flavor to everything from killer cocktails to luscious sauces.

When Jean-Georges Vongerichten was growing up in Alsace, in Eastern France, there were no soft drinks in his mother's refrigerator. "Instead, we mixed sparkling water with syrups," says the four-star chef with 18 restaurants from New York City and Las Vegas to Bora-Bora. "Mint, grenadine, orgeat (almond syrup), cassis, lemon." Today he still mixes his own drinks with syrups made ahead of time—margaritas spiked with homemade ginger-lime syrup, for one, and lemonade flavored with lemon-thyme syrup. His real genius, though, is seeing a syrup's possibilities beyond drinks. He whisks his ginger-lime syrup into a dressing for juicy sesame-crusted chicken breasts. Lemon-thyme syrup becomes a base for sorbet. A savory mushroom syrup made by simmering fried mushroom stems in chicken broth (no sugar added) gets drizzled over moist pan-seared salmon fillets to form an earthy sauce.