Onion powder is a seasoning made from dried, ground onions. It has a mild and slightly sweet flavor that adds depth to many dishes without overpowering them with strong onion taste. Onion powder can be used in cooking, baking or as a condiment, and it's commonly found in recipes for meatloaf, hamburgers, soups, stews, and sauces. It is also used to flavor dips, marinades, salad dressings, and bread mixes.