Drain Pears, Reserving Juice In A 1-Cup Measuring Cup. Add Enough Water To Measure 3/4 Cup. Set Pears Aside. In A Small Bowl, Combine The Pear Juice Mixture, Apple Juice, Brown Sugar, Soy Sauce And Garlic Powder; Set Aside. In A Large Skillet, Saute Chicken In Oil For 4-6 Minutes Or Until No Longer Pink. Add Parsley And Pear Juice Mixture. Cover And Simmer For 5-7 Minutes, Stirring Occasionally. In A Small Bowl, Combine Cornstarch And Cold Water Until Smooth; Pour Into Skillet. Bring To A Boil; Cook And Stir For 1 Minute Or Until Thickened. Stir In Walnuts And Pears. Serve Over Rice If Desired.