Cajun Shrimp and Pasta

Cook pasta according to package directions, omitting salt and fat; drain.

Heat butter in a large nonstick skillet over medium-high heat, stirring until butter melts. Add onion, and cook, stirring constantly, 3 minutes. Add shrimp, Cajun seasoning, and salt; cook 3 minutes or until shrimp are done, stirring constantly.

Remove from heat. Serve shrimp mixture over pasta. Add water to pan drippings, and cook over high heat 30 seconds; pour evenly over each serving.