In large skillet, bring water, milk and margarine to a boil; reduce heat to medium.

Slowly stir in pasta, seasonings, and onion. Separate pasta with a fork, if needed. Return to a boil. Boil uncovered 3 minutes. Add peas; continue boiling 1 to 2 minutes or until pasta is tender, stirring frequently.

Remove skillet from heat. (Sauce will be thin.) Stir in ham and sour cream. Let stand 3 to 5 minutes for sauce to thicken.