First, pour water into a large pot and bring the water to a boil. Meanwhile, peel the potatoes and cut them into 1-2 inch cubes. Place them in the large pot, bring the boil down to a simmer, and cover with a lid. Cook the potatoes for about 25 minutes or until a fork cuts through them easily.
Once the potatoes have finished cooking, drain the water and set them aside.
Mix together the softened butter with the minced garlic. Then add the heavy cream, butter, and sour cream to the potatoes and mix with a hand mixer until pureed. You may have to add more heavy cream to get the extra smooth consistency.
Add salt and pepper to taste. Serve hot and enjoy.