Preheat the oven to 425°. Slice off and discard the top of the head of garlic. Drizzle the head with 1 tablespoon of olive oil. Wrap the head in aluminum foil and place in the oven until softened and fragrant, about 45 minutes. Reserve two of the cloves for the dressing and save the rest for another use.
In a blender, combine the 2 garlic cloves, chives, dill, parsley, basil, mayonnaise, anchovy fillets, lemon zest, yogurt, avocado, water and hot sauce and pureé until smooth. Season with salt and pepper; if the purée is too thick, add a touch of lemon juice or water.