Roast Garlic:
Preheat oven to 400ºF. Trim ¼ inch off the top of each garlic bulb. Place bulbs cut-side up on foil, drizzle with olive oil, sprinkle with salt, and wrap tightly. Roast for 45–60 minutes, or until golden and tender. Let cool slightly, then squeeze cloves out of skins.

Boil Potatoes:
Cut potatoes into 1–2 inch chunks and place in a large pot of cold water, making sure water covers potatoes by at least 1 inch. Add 2 tsp sea salt. Bring to a boil, then cook for 15–20 minutes, until potatoes are easily pierced with a knife. Drain and shake off excess water.

Prepare Cream Mixture:
In a medium saucepan, combine roasted garlic cloves, mascarpone, milk, butter, and 2 tsp sea salt. Heat over medium, whisking until warm and smooth (do not boil).

Mash Potatoes:
Return drained potatoes to the pot. Mash to desired consistency (chunky or smooth). Pour warm garlic-mascarpone mixture over the mashed potatoes and mix until fully combined.

Serve:
Transfer to a serving bowl and garnish with fresh herbs and cracked black pepper.