Blue Cheese Salad Dressing

2 cups mayonnaise
1 cup (8 ounces) sour cream
1/4 cup white wine vinegar
1/4 cup minced fresh parsley
1 garlic clove, crushed
1/2 teaspoon ground mustard
1/2 teaspoon salt
1/4 teaspoon pepper
4 ounces crumbled blue chees

Place all the ingredients in a blender; cover and process until smooth. Store in the refrigerator. Makes 3 cups.