Whisk 1/4 cup plain kefir and 1/4 cup crumbled blue cheese together vigorously until the mixture resembles small curd cottage cheese. Stir in 1/4 cup mayonnaise,1/4 cup plain Greek yogurt,2 teaspoons white wine vinegar,1/4 teaspoon salt,1/4 teaspoon garlic powder, and 1/8 teaspoon black pepper. Refrigerate until ready to use, up to 3 days.
Salad
Tear 3 Romaine hearts into bite-sized pieces. Wash and dry the lettuce.
Divide the lettuce equally among 4 bowls. Top with tomato wedges and carrot. Drizzle each bowl with blue cheese dressing.
Whisk together 2 Tablespoons unsalted butter (melted) and 1/4 cup hot sauce in a medium bowl until uniform. Add 2 cups shredded rotisserie chicken and toss to coat. Top each bowl of salad with 1/2 cup of hot sauce coated shredded chicken. Garnish with additional blue cheese, if desired.