Yield: 1 Cup
1/2 c Sugar
1/4 c Dry mustard
1 ds Salt
1 large Egg
1/3 c Apple cider vinegar
Combine all ingredients in container of an electric blender; process 20 seconds or until smooth, stopping once to scrape down sides. Pour mixture into a heavy saucepan.
Cook over medium heat, stirring constantly, 5 minutes or until mixture is thickened; cool completely.
Serve this mustard as a dip for pretzels.