In a small measuring cup, combine the milk, lemon juice, and garlic. Pour over the blue cheese in a small bowl.
1/2 cup milk, 2 tablespoons lemon juice, 1 clove garlic, 6 ounces blue cheese
With the back of a fork mash up the blue chese, milk, lemon juice, and garlic. The consistency will be a bit lumpy, but the goal is the minimize large chunks of the cheese in the salad dressing. You are looking for a consistency similar to cottage cheese.
Stir in the remaining ingredients. Add more salt and pepper to taste.
1/2 cup sour cream, 1/3 cup mayonnaise, 2 tablespoons white vinegar, 1/2 teaspoon sugar, 1/2 teaspoon salt, 1/2 teaspoon black pepper
Store in an airtight container for up to 4 days. Stir before using.