Chef John's Dijon Mustard Recipe

Combine white wine water vinegar onion and garlic in a saucepan; bring to a boil reduce heat to medium low and simmer until flavors combine about 15 minutes. Cool to room temperature and pour through a strainer into a large bowl; reserve liquid and discard onions and garlic.

Stir mustard seeds dry mustard garlic powder and salt into strained liquid; cover the bowl with plastic wrap and let sit at room temperature until mixture thickens 24 to 48 hours.

Puree mustard mixture to desired consistency using a stick blender. Transfer mustard mixture to a saucepan and add water as necessary to reach a smooth consistency. Bring mustard to a simmer reduce heat to medium and cook stirring constantly until flavors combine about 10 minutes.

Pack mustard into hot sterilized jars filling to within 1/4 inch of the top. Run a knife or thin spatula around the insides of the jars after they have been filled to remove any air bubbles. Wipe the rims of the jars with a moist paper towel to remove any food residue. Top with lids and screw on rings.

Refrigerate mustard until flavors blend at least 1 week.