Korean spinach salad

1 pound fresh spinach3 hard-cooked eggs, diced6 to 8 slices crisp-cooked bacon, crumbled2 cups fresh bean sprouts1 (8 ounce) can water chestnuts, slicedDressing1 cup oil2/3 cup granulated sugarSalt, to taste1 medium onion, grated1/4 cup vinegar1/3 cup catsup1 tablespoon Worcestershire sauceTrim and discard tough spinach stems. Rinse leaves well; pat dry and break into bite-size pieces in a salad bowl. Add remaining salad ingredients. Mix dressing ingredients together. Toss salad with dressing.