Stir together gingersnap crumbs and melted butter in a medium bowl. Press mixture evenly into a greased 13- x 9-inch pan. Carefully spread condensed milk over crumb mixture.
Combine peanut butter chips and remaining 3 ingredients in a medium bowl. Sprinkle mixture evenly over condensed milk; gently press mixture down.
Bake at 350° for 25 to 30 minutes or until lightly browned. Cool in pan on wire racks. Cut into squares.
Irene E. Souza, Cupertino, CA