Line pan with 40 saltines. Bring to boil: 2 sticks butter and 1 cup brown sugar. Boil 3 minutes, stirring constantly (rolling boil). Pour over saltines and bake 5 minutes. Sprinkle 1 (12 ounce) package chocolate chips over top and smooth. Add 1 cup ground pecans, almonds and/or walnuts. Sprinkle on top. Refrigerate 2 hours. Peel off foil and break into pieces.