Red onion powder is the ground form of dehydrated red onion. It is an excellent replacement for fresh onion. Toss it into spice rubs and spice blends, dressings, dips, frying batter mixes, sauces, soups, stews, salads, sauces, curries etc and making your cooking experience easy and fun.Onion powder is a seasoning made from dehydrated ground onions. This potent-smelling spice is most often used in dry rubs and in marinades to get concentrated onion flavor without the moisture and bulk of the onion bulb itself.