3/4 cup buttermilk
1/4 cup low-fat mayonnaise
2 tablespoons white wine vinegar
2 tablespoons minced fresh assorted herbs  
1 garlic clove (about 1/2 to 1 teaspoon), minced, or to taste 
1 teaspoon onion powder, or to taste
Salt and pepper to taste

Preparation

In a bowl, whisk together all the ingredients

(asst herbs: chiles, tarragon, parsley, chives, oregano, etc.)