Preheat oven to 350°F.
Spray a shallow baking pan with cooking spray. Lay the graham crackers close together in a single layer on the pan.
Melt the butter in a saucepan over medium-low heat and add the sugar, stirring constantly. Bring to a boil. Then cook for two more minutes, continuing to stir. The mixture will become frothy and thicken.
Pour the mixture over the graham crackers and spread it evenly. Sprinkle the nuts on top.
Bake for eight minutes. Allow to cool and use a spatula to remove the crackers from the pan. Break the crackers into bite-size pieces for your eager little beaver.
Makes about 12 servings.