Preheat the oven to 350 degrees F.
Line a large baking sheet with sides with aluminum foil. Pour the butter onto the lined sheet. In a large bowl, mix the egg whites, sugar and cinnamon. Add the pecan halves and toss until they are fully coated. Spread the pecans onto the baking sheet. Bake for 30 minutes, stirring the pecans every 10 minutes. Cool on the baking sheet for 10 to 15 minutes before serving.
Recipe adapted from Georgia Cooking in an Oklahoma Kitchen by Trisha Yearwood (c) Clarkson Potter 2008