Prepare dressing by whisking together sour cream, buttermilk, and lemon juice in a small bowl. Sprinkle kief or hash over the mixture and whisk to combine. Stir in blue cheese, salt, pepper, and chives.
Wash lettuce and cut in quarters. Place one quarter on each of 4 salad plates. Drizzle dressing over lettuce wedges and sprinkle crumbled bacon, diced tomatoes and avocado on top and around the plate. Serve immediately.
Store leftover portions of dressing in the refrigerator for up to 3 days.