Preheat oven to 350 degrees.
In a medium saucepan, melt butterscotch chips and butter or margarine. Stir in graham cracker crumbs and nuts. Press half of this mixture firmly into the bottom of a greased 9- by 13-inch baking pan.
In a large mixing bowl, beat cream cheese until fluffy. Beat in condensed milk, vanilla and egg. Mix well. Pour this mixture onto the crust in pan. Top with remaining crumb mixture.
Bake 25 to 30 minutes or until toothpick inserted near the center comes out clean. Cool to room temperature. Chill before cutting into bars. Refrigerate leftovers
Recipe submitted by ~Donna~ V on 3/23/00