Fill a stockpot 3/4 the way with water and heat on high. Season with a tablespoon of kosher salt. Bring to a boil. Add the sweet potatoes and boil for 30 minutes. (TIP: You can also boil these in chicken stock or veggie stock for extra flavor!) Drain and set aside.
Preheat the oven to 375 F. Heat a sauce pan over medium high heat. Add the heavy cream and bring it to a boil, then reduce to a simmer. Add 5 oz (about 2/3) of the Aged Havarti and stir until combined and melted. Let the mixture bubble until thick. If it’s not silky, feel free to add a little more heavy cream.
Mash the sweet potatoes with a masher or ricer and place them in a mixing bowl. Pour the hot cheese mixture into the mashed sweet potatoes and mix until combined. Pour the mashed sweet potatoes into a baking dish. Top with the remaining 2 oz of cheese. Bake for 10-15 minutes, until the cheese is melty and golden brown. If it’s not golden brown, feel free to just broil it on low for 1-2 minutes until golden. Enjoy immediately!!