Sour Cream (Best Option)
1:1 (1 tablespoon sour cream per 1 tablespoon Greek yogurt)Sour cream contains lactic acid and a creamy consistency similar to Greek yogurt, which helps maintain the tangy and smooth characteristics important in teriyaki sauce. The acidity helps cut through the sweetness and soy-based saltiness, preserving the intended flavor harmony.
For best results, use full-fat sour cream to match the richness of Greek yogurt and whisk it well into the sauce to avoid curdling. Avoid overcooking after adding to prevent separation.
Compared to Greek yogurt, sour cream may impart a slightly richer mouthfeel and a marginally different tang profile, but it will not significantly alter the overall taste or texture of the teriyaki sauce.