Put sweet potatoes, unpeeled, in a large saucepan. Cover with 2 inches of cold water. Add 1 Tbsp salt and bring pot to a boil. Reduce heat to medium high and cook for about 40 minutes, until tender. Allow to cool slightly, then peel. If using leftover potatoes, microwave them until they are heated through. Pass through a ricer into a large bowl.

Meanwhile, bring a separate large pot of water to a boil with 1 Tbsp salt.

Add flour, egg, kosher salt, and black pepper to the potatoes. Using your hands, gently combine the ingredients until the dough is smooth and soft.

Lightly dust your work space with flour. Divide dough into 4 pieces. Roll each ball into a long snake about 3/4 inches thick. Cut your rope into 1 inch pieces. Place the finished gnocchi onto parchment paper or cookie sheets, sprinkled with flour.

Place half the gnocchi into the salted boiling water in the large pot. Cook for 2-3 minutes until gnocchi rises to the surface. Using a large slotted spoon remove gnocchi. Repeat with other half.

For the browned butter sauce, in a sauce pan melt the butter and salt over medium low heat. Add garlic and rosemary and cook for about 5 minutes or until the butter begins to brown. Add the 2 Tbsp heavy cream and stir to combine. Remove from heat and add Parmesan cheese. Immediately toss with the gnocchi. Top with additional Parmesan cheese.