Roast and prepare the garlic. Slice off the top of the garlic head, drizzle with olive oil and wrap losely in foil. Place in a preheated oven at 350 degrees and roast for about 45 minutes or until soft and golden.
When garlic is done carefully remove it from the oven, open the foil, and let it cool slightly. Squeeze the roasted cloves out of their skins and mash them with a fork until smooth and creamy.
Peel the potatoes, rinse them, and cut into even chunks. Place in a large pot, cover with cold water, and add a teaspoon of salt. Bring to a boil and cook for about 20 minutes or until the potatoes are tender when pierced with a fork. Drain most of the water from the potatoes, leaving a small amount in case you need to adjust the texture later. Begin mashing the potatoes while they’re still hot.
Add the butter, heavy cream, and black pepper. Continue mashing and stirring until the potatoes are smooth and creamy. Stir in the roasted garlic paste and mix until everything is well combined. Taste and adjust salt if needed. Serve immediately while warm, topped with a pat of butter and fresh herbs if desired.