Bring 4 quarts of water to a boil, in a large pot, over high heat. When the water is boiling, add 2 tablespoons salt and spaghetti. Reduce heat to medium-high and cook, uncovered, according to package directions, stirring occasionally.

Meanwhile, in a medium saucepan, warm the Tomato Meat Ragu over low heat, stirring occasionally. When spaghetti is cooked, drain and return it to the cooking pot. Toss with warm Tomato Meat Ragu and butter. Sprinkle with Parmesan cheese. Serve warm.