Best Ever Slaw Dressing

1 cup sugar
½ cup vinegar
1 cup salad oil
1 tsp. celery seed
1 tsp. salt (I use a little less.)
1 tsp. dry mustard
1small onion, finely diced

Beat all ingredients together in mixer until very creamy. Store covered in pint jar in refrigerator. Keeps well up to a week.
(One half of above recipe makes more than enough for two people.)