Slice off the top of the garlic head. Drizzle head with olive oil and wrap in foil. Place on a sheet tray and bake until tender and fragrant, roughly 35 minutes. Remove from the oven and let cool. Remove the cloves and mash with a wooden spoon.
Place potatoes in a large stockpot and cover with cold water.
Add salt and bring to a boil. Cook until fork tender and drain.
Mash the potatoes until smooth.
Meanwhile heat butter and cream until butter melts.
Add the roasted garlic and potatoes and mash all together.