Preheat Oven To 450 Degrees F. Line A Baking Sheet With Aluminum Foil And Spray With Non-Stick Cooking Spray. Put Cereal And Walnuts Into A Zip-Top Plastic Bag. Press Air Out Of Bag And Zip Closed. Using A Rolling Pin Or Heavy Food Can, Press And Roll Over Ingredients In The Bag Until Cereal Is Finely Crushed And Walnuts Are In Pieces As Small As Grains Of Rice. Add Garlic Powder, Salt And Pepper To Bag. Shake To Mix. Crack Egg Into Medium-Size Bowl. Beat With A Fork Until Yolk And White Are Mixed Together. If Using Chicken Breasts, Place Chicken On Cutting Board. Cut Into 1/2-Inch Wide Strips Across The Short Direction Of Each Piece Of Chicken. Add Sliced Chicken (Or Tenders) To The Egg And Stir. Immediately Wash Hands, Knife And Cutting Board With Warm Soapy Water. With A Fork, Remove Chicken Pieces Letting Extra Egg Drip Off. Put Chicken Into Bag With Walnut Mixture. Close Bag. Gently Shake Bag Back And Forth, And Press Walnuts Onto Chicken. Pour Chicken Onto Prepared Pan And Use A Fork To Separate Pieces So They Aren'T Touching Each Other. Wash Hands Again If You Touched The Chicken. Bake 10 Minutes Until Crumbs Are Golden Brown And Chicken Is Cooked Through. To Check If Chicken Is Done, Remove One Piece And Cut In Half. It Should Be White All The Way Through, Not Pink.