Add all dry ingredients together and mix: mustard seeds, salt, white pepper, all spice. Add shallot / onion and mix. Add white wine vinegar and mix. Add white wine and mix. Cover with plastic wrap and refrigerate for at least 8 hours.
Add mix to blender or food processor. Blend until thickness and chunkiness desired. Taste and add brown sugar if too bitter for your taste.
Store in a small mason jar in refrigerator for up to 2 weeks to 2 months. See notes.
Notes
You can omit the wine for water to remove any alcohol content for children or pregnancy. *This recipe makes spicy Dijon mustard. To adjust the heat, reduce the amount of brown mustard seeds. If too bitter, add 1/2-1 teaspoon of brown sugar.While this mustard can last for up to a couple of months, you do want to check it for spoilage. Once it starts to dry up,darken, or begin to separate, then you should not consume.