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red onion -- sliced

ProduceRed onions are typically harvested in late summer through fall; however, improved storage methods make them available year-round in most markets, with peak freshness from August through October.

Red onions are low in calories and provide vitamin C, dietary fiber, and quercetin, a flavonoid antioxidant. The anthocyanin content offers additional antioxidant benefits, particularly when consumed raw.

About

Red onions (Allium cepa var. rubrum) are bulb vegetables belonging to the allium family, native to Central Asia and cultivated worldwide. Characterized by deep purple-red outer skin and reddish-purple flesh with white rings, red onions possess a milder, slightly sweet flavor profile compared to yellow onions, with subtle fruity and peppery notes. The red pigmentation comes from anthocyanin compounds, water-soluble pigments that intensify in acidic conditions. Common varieties include Burgundy, Red Spanish, and Italian Red onions, each with slight variations in size, sweetness, and storage capability.

Culinary Uses

Red onions are widely used in raw applications where their visual appeal and mild sweetness are assets: salads, salsas, pickled preparations, and ceviche. When sliced, they are commonly incorporated into sandwiches, grain bowls, and cold vegetable dishes. Cooking red onions—whether caramelized, roasted, or grilled—develops their natural sugars and mellows peppery notes, making them suitable for soups, stews, and side dishes. The sliced form in particular is ideal for quick pickling (with vinegar and spices), raw consumption in fresh preparations, and charring for grilled applications. They pair well with citrus, vinegar-based dressings, and roasted or grilled proteins.

Forms & Preparations

Sliced — Thin to medium cuts across the onion, used raw in salads and on sandwiches, or for quick cooking and caramelization.
Diced — Small, uniform cubes used in salsas, grain bowls, and for even cooking in various preparations.
Rings — Thin circular slices popular for garnishing, pickling, or charring on a grill.
Pickled — Sliced onions preserved in vinegar and spices, used as a condiment or garnish with sharp, tangy flavor.
Caramelized — Slowly cooked until deep brown and sweet, used for soups, burgers, and side dishes.
Roasted or grilled — Whole or halved bulbs exposed to high heat until tender and charred, softening the onion's sharp bite.