Place the Dijon mustard, yellow mustard, honey, and mayonnaise into a medium mixing bowl or the jar of an immersion blender. These form the creamy, sweet-mustard foundation of the sauce.

Whisk vigorously (or blend briefly with an immersion blender) until the mixture is uniformly smooth and slightly thickened, about 20–30 seconds by whisk or 5–10 seconds by blender.

Acidity & Seasoning

Add the apple cider vinegar and fresh lemon juice to the base mixture to brighten the flavor. Stir or pulse to combine.

Stir in the prepared horseradish if using, then add the garlic powder, onion powder, salt, and black pepper. Mix thoroughly and taste.

Adjust seasoning as needed: add up to another 1/2 teaspoon honey if you prefer it sweeter, or another 1/2 teaspoon vinegar or a few more drops of lemon juice if you prefer more tang.

Finishing & Optional Adjustments

If you want a silkier, more emulsion-like texture, slowly whisk in the extra-virgin olive oil in a steady stream until fully incorporated. Alternatively, add the oil and blend briefly with the immersion blender.

If the sauce is too thick for your use (dipping vs. dressing), whisk in water, 1 tablespoon at a time, until you reach the desired consistency. Up to 2 tablespoons usually turns it from a thick dip to a pourable dressing.

Transfer the sauce to a clean jar, garnish with chopped fresh chives if desired, and seal. Chill in the refrigerator for at least 30 minutes to allow flavors to meld. Serve cold or at cool room temperature.

Storage: Keep refrigerated in an airtight container for up to 10 days. Stir before use; if separated, shake or whisk to re-emulsify.