Fermented Mustard

Mustard fermented with whey or brine — tangy, complex, alive. It tastes like a better version of every mustard you've ever had. Takes 3 days of patient waiting and then it's yours forever. Spread it on everything.

What You Need

• ½ cup yellow mustard seeds
• ¼ cup brown mustard seeds
• ⅓ cup apple cider vinegar
• 3 tbsp filtered water
• 1 tbsp whey (from yogurt or kefir) or liquid from sauerkraut brine
• 1 tbsp raw honey or maple syrup
• 1 tsp fine salt
• ½ tsp ground turmeric (optional — for color and earthiness)

Method

1. Combine mustard seeds, vinegar, and water in a jar. Make sure seeds are fully submerged.
2. Add whey or brine. Stir. Seal loosely.
3. Leave at room temperature for 2–3 days. The seeds will absorb most of the liquid and soften.
4. Transfer to a blender or food processor. Add honey, salt, and turmeric. Blend to your desired texture — fully smooth, coarsely ground, or somewhere between.
5. Taste and adjust — more vinegar for bite, more honey for sweetness, more salt for depth.
6. Transfer to jars and refrigerate. The flavor deepens over the first week.

Tips & Notes

• The whey or brine inoculates it with beneficial bacteria — this is what makes it a living ferment rather than just homemade mustard.
• Keeps refrigerated for 3+ months. Gets noticeably better after the first week.
• No whey? Skip it and just use the ACV — it still makes exceptional mustard, just not fermented.

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