Cook the pasta according to directions. Reserve 1/4 cup of pasta water. Melt the butter in a medium saucepan over medium-high heat. Add shallots and saute until tender, about 3-5 minutes. Add cream to pan and bring to a boil. Cook about 5 minutes, until sauce reduces slightly. Add cooked pasta, reserved pasta water, and half of the Parmesan cheese. Stir well to combine and melt cheese. Season with salt and pepper. Sprinkle with remaining Parmesan and serve immediately.