Thoroughly grease cookie sheet and cover with graham crackers. In small saucepan melt butter and butter. As it melts, pour in sugar. Bring to a boil and cook 10 minutes, stirring as needed to keep from sticking and burning. Stir in pecans. Quickly spoon onto graham crackers, smoothing out with a spatula; it will thicken fast. Place in preheated 350 degree oven and bake for 10 minutes. Remove from oven and cool. Loosen with a spatula. Remove from pan and break into serving size pieces.