Step 1

Steam or boil cauliflower and garlic until soft.

Step 2

Drain the cauliflower, then add buttermilk, butter, salt, pepper and purée with an immersion blender. (If you don't own a hand blender, you should consider getting one. It is one of my most used gadgets in my kitchen, you'll wonder how you ever lived without it!) A regular blender would work fine as well.