1 cup light or dark mustard seed
4 Tbsp dry mustard powder, lightly packed
1 cup water
2/3 cup balsamic vinegar
6 Tbsp white wine vinegar or rice vinegar
4 Tbsp sugar
4 tsp salt (or less, to taste)
2-4 cloves garlic (or more, to taste)
Grind
the mustard seed finely in a spice mill, blender, or mortar. (If using
a blender, add the mustard powder to facilitate the grinding.) Combine
ground mustard seed, dry mustard powder and water in a bowl, and mix
thoroughly. Let stand, uncovered, for at least 1 hour or up to 4 hours,
and stir occasionally. Scrape the mixture into a blender or food
processor and add the balsamic vinegar, white wine or rice vinegar, and
the sugar, salt and garlic. Process until the garlic has been
incorporated and the mustard is fairly smooth. Store in clean, dry
jars, tightly capped, in a cupboard. The mustard will be ready to use
in a few days.