Green peppercorns are the unripe berries of the pepper vine (Piper nigrum), the same plant that produces black, white, and pink peppercorns; the color comes from harvesting the berries before they ripen and turn red, then preserving them fresh, brined, or dried rather than letting them dry naturally to black. Native to India's Malabar Coast, pepper has been cultivated there for millennia; today Thailand, India, and Vietnam are leading producers.
Their flavor is brighter, grassier, and less pungent than black or white pepper. They season sauces, marinades, and stir-fries in Thai, Cambodian, and Vietnamese cooking, and are the defining ingredient in French sauce au poivre vert, served with steak and other grilled meats.
Fresh green peppercorns should be used within a few days; brined or dried versions keep much longer. They pair well with citrus, garlic, ginger, and rich cream sauces.