Creamy Cauliflower Mash

8 cups bite-size cauliflower florets (about 1 head)
4 cloves garlic, crushed and peeled
1/3 cup buttermilk
4 teaspoons extra-virgin olive oil, divided
1 teaspoon butter
1/2 teaspoon salt
Freshly ground pepper to taste
Snipped fresh chives for garnish

Place cauliflower florets and garlic in a steamer basket over boiling water, cover and steam until very tender, 12 to 15 minutes. (Alternatively, place florets and garlic in a microwave-safe bowl with 1/4 cup water, cover and microwave on High for 3 to 5 minutes.)

Place the cooked cauliflower and garlic in a food processor. Add buttermilk, 2 teaspoons oil, butter, salt and pepper; pulse several times, then process until smooth and creamy. Transfer to a serving bowl. Drizzle with the remaining 2 teaspoons oil and garnish with chives, if desired. Serve hot.