Orange bitters are a zesty, aromatic cocktail ingredient made from a blend of dried orange peels, spices (like gentian root, coriander, and cardamom), and high-proof alcohol, used to add citrusy depth and complexity to drinks like Old Fashioneds, Martinis, and Manhattans, and even savory dishes. They provide a bright, citrus-forward flavor that balances sweetness and bitterness, making them a versatile staple in mixology. Bright, citrusy, and aromatic with notes of orange, often with underlying spice and a bitter finish.