Preheat oven to 325°. In a bowl beat egg whites till frothy, add vanilla and pecans, stir nuts until coated with egg white mixture. Add in cinnamon, cayenne pepper, and sugar, stir well. Spread pecans evenly onto a baking pan greased with non-stick cooking spray. Bake for 25 minutes, stirring once after 10 minutes. Allow pecans to cool completely before serving. Store any leftovers in an airtight container.
Note: You can use 1/2 cup Xylitol (which is an all natural sugar substitute), in place of sugar.