01 -
Bring a large pot of salted water to a boil.
02 -
Add the cauliflower and boil until knife-tender, about 10 minutes.
03 -
Drain the cooked cauliflower well.
04 -
Transfer cauliflower to a food processor. Puree with butter, garlic, mustard, salt, and pepper.
05 -
Season to taste and garnish with chives if desired.