1Cook pasta as directed on package; drain. Cover to keep warm.
2Meanwhile, in 10-inch skillet, cook ground beef over medium-high heat, stirring frequently, until thoroughly cooked; drain. Stir in pasta sauce and water. Reduce heat to medium; simmer uncovered 5 minutes.
3Stir in cooked pasta. In small bowl, mix sour cream and cheese. Spoon over pasta mixture. Reduce heat to low; cover and cook 6 to 8 minutes or until thoroughly heated.