This depends on your taste. If you want a more mild blue cheese-flavored dressing, choose more white crumbles. If you want a stronger blue cheese flavor, choose a brand that has more blue in the crumbles. This will give the dressing more of that strong, sharp, blue cheese taste. For the boldest blue cheese flavor, use a wedge of Roquefort cheese and crumble it by hand. It takes a little more time, but the flavor is worth it!