Mix the mustard, ginger and soy sauce, blending well. Blend in the sesame oil, sesame seeds, pepper and green onion, blending thoroughly.
Blend in the sour cream. Cover and chill. Makes about 1 1/4 cups of dip. Suggested Dippers: Chicken Strips Or Cubes, Fried Wonton, Noodle Chips, Bok Choy