Pour water into a medium pot to a depth of 1/4"
Add cauliflower and garlic and cover pot
Bring to a boil and cook until florets are easily pierced with a paring knife, about 8 minutes
8 Minutes
Drain well and transfer to a food processor
Add milk, butter, 1 tsp. salt, and 1/2 tsp. pepper
Purée until smooth, adding more milk if needed
Season to taste with salt and pepper
Top with chives, if using