Cook Fettuccine According To Package Directions. Meanwhile, In A Large Skillet, Saute Ham In Oil Until Lightly Browned. Remove With A Slotted Spoon And Set Aside. Add Onion To Skillet; Saute For 4 Minutes. Add Mushrooms; Saute 3 Minutes Longer. Stir In The Flour, Rosemary And Pepper Until Blended. Gradually Add Milk. Bring To A Boil; Cook And Stir For 2 Minutes Or Until Thickened. Reduce Heat; Add Peas And Sour Cream. Cook 2 Minutes Longer. Drain Fettuccine; Stir Into The Mushroom Mixture. Add Ham; Heat Through.