Tortellini in Parmesan Cheese Sauce 1 (16 ounce) package frozen cheese tortellini 1/3 cup butter or margarine 1 teaspoon flour 1/2 cup milk 1/2 cup grated Parmesan, mozzarella,     Romano or Monterey Jack cheese 2 tablespoons chopped fresh parsley (optional) Cook tortellini according to package directions; drain. Meanwhile, for sauce, heat milk in a medium saucepan. While milk is heating, melt butter in a separate bowl in microwave. Stir flour and butter together. Add mixture to milk; cook and stir until slightly thickened and bubbly. Add cheese; cook and stir until well blended. Salt and pepper to taste. Pour over tortellini; stir gently. If desired, sprinkle with parsley.