Total time: 15 minutes, plus overnight soaking time for the mustard Servings: This makes about 1 2/3 cups mustard About ¼ cup plus 3 tablespoons (2½ ounces) brown mustard seeds Scant ¼ cup (1¼ ounces) black mustard seeds About ¼ cup plus 2 tablespoons (1¼ ounces) mustard powder 1/2 cup cider vinegar 3/4 cup flat hard apple cider 1 1/2 teaspoons kosher salt 2 1/2 tablespoons sugar 1 Granny Smith or similar tart apple, peeled, cored and finely chopped 1. Soak the mustard seeds: Place the mustard seeds and powder in a medium glass or ceramic bowl along with the cider vinegar and hard cider. Set aside, covered (but not sealed airtight), for 24 hours. 2. Place the mixture in a food processor along with the salt and sugar, and process for 1 to 2 minutes until the seeds are coarsely ground. Add the chopped apple and pulse a few times to incorporate. This makes about 1 2/3 cups mustard. 3. The mustard will be very pungent at first. Cover and refrigerate for a few days (or to taste) before using. Each tablespoon: 41 calories; 2 grams protein; 4 grams carbohydrates; 1 gram fiber; 2 grams fat; 0 saturated fat; 0 cholesterol; 2 grams sugar; 65 mg sodium.