McCormick Bulk Onion Powder at .com. Onion may be grown in almost any temperate climate. Onion is an important flavoring in almost every country in the world. When combined with other ingredients, onion’s flavor is rarely overwhelming or assertive. McCormick’s dehydrated onion varieties, including Onion Powder, reconstitute in liquid, providing consistently fresh flavor while maintaining a longer shelf life. 20 oz. Container