Place potatoes and 1 tablespoon salt into a large pot and cover with water; bring to a boil. Reduce heat to medium, cover, and simmer until fork-tender about 25 to 35 minutes. Drain potatoes.

While potatoes are cooking, combine heavy cream and butter in a small saucepan over medium-low heat until heated through and butter is melted, about 5 minutes.

Slowly pour 1 cup of the cream-butter mixture into the potatoes. Season with 2 teaspoons salt, black pepper, and garlic powder. Using a hand masher begin to mash the potatoes. Continue mashing and adding a little cream until the desired consistency is reached.

Cut one box of Boursin cheese into cubes then fold into the potatoes.

Spoon potatoes into your serving bowl. Divide the other box of Boursin cheese in half and swirl on top the potatoes, garnish with chopped chives.