Place shredded cabbage, red pepper, onion, carrot, celery and 2 tablespoons sugar in a bowl. Combine vegetables and refrigerate for 1 hour.
Meanwhile, prepare dressing. Place oil, vinegar, ½ cup sugar, mustard, salt and pepper in a saucepan. Cook over medium heat and bring to a boil for 2 minutes. Remove from heat and cool. Drain cabbage and vegetables to eliminate excess liquid and transfer to a salad bowl. Toss salad with dressing.
This salad may be kept in the refrigerator for several days.