01 - Preheat the oven to 400°F. Slice the top off the garlic bulb to expose the cloves, drizzle with olive oil, wrap in foil, and roast for 30 minutes until soft and golden.
02 - Bring a large pot of water to a boil. Add cauliflower florets and cook for 10 to 12 minutes until tender. Drain thoroughly.
03 - In a large bowl or food processor, combine the cooked cauliflower, roasted garlic cloves squeezed from skins, butter, sour cream, milk, salt, and pepper. Mash or blend until smooth and creamy.
04 - Fold in most of the chopped chives, reserving a few for garnish. Adjust seasoning as needed.
05 - Transfer to a serving dish, sprinkle with remaining chives, and serve warm.