Stir the ingredients together until well blended. Spoon into a jar or small bag and attach the directions below.
Directions for the tag
Stir the mix into the sour cream until well blended. Cover and refrigerate for at least 1 hour so the onion softens. Serve with potato chips, crackers, or fresh vegetables.
Notes
Use shelf-stable grated Parmesan, the kind sold in a shaker canister, not freshly shredded cheese.