⭐ Buttermilk (reduced) (Best Fat-Free Option)
1 teaspoon buttermilk mixed with 1 tablespoon unsalted butter per egg yolk Quick tip: Adds acidity but is thinner, so combining with butter helps mimic the creamy texture.
Buttermilk provides the necessary acidity to balance the richness of Hollandaise but is much thinner than Greek yogurt. Mixing it with butter increases fat content and viscosity, helping to maintain the sauce's creamy consistency.
Incorporate the mixture slowly and whisk constantly to ensure proper emulsification. Be cautious with heat, as buttermilk can cause curdling if overheated.
The final sauce will be tangy but slightly less thick and creamy than when using Greek yogurt, with a lighter mouthfeel.