Roasted Garlic Mashed Potatoes

INGREDIENTS

• 1 head garlic
• 1 teaspoon olive oil
• 4 medium russet potatoes, skin-on scrubbed (for creamy mashed potatoes, peel the potatoes)
• 3-4 tablespoons butter
• 1/4-1/2 cup milk or heavy cream (or more)
• 1 1/2 teaspoons kosher salt (or 3/4 teaspoon table salt)
• 1 teaspoon minced fresh chives