This is how to make authentic Yum Yum sauce like the popular Japanese Steakhouse Sauce! Yum Yum sauce is a Hibachi restaurant condiment typically made in-house from mayonnaise, ketchup, apple cider vinegar, and sugar. It's sweet and tangy, and the most delicious over Fried Rice, smothered over vegetables, or dipped into chicken! You'll love this homemade dipping sauce!