Preheat the oven to 350?F.
Combine the butter, graham cracker crumbs, and brown sugar in a large bowl, mixing well. Press the mixture against the bottom and sides of a 12 X 17-inch baking pan. Sprinkle the pecans over the crust. Sprinkle the chocolate chips over the pecans. Sprinkle the coconut over the chocolate chips. Sprinkle the peanut butter chips over the coconut. Drizzle the condensed milk evenly over the top of the chips. Bake until the edges are brown and crusty and the coconut is lightly toasted, 20 top 25 minutes. Remove from the oven and let cool completely.
Cut into 20 squares. Put 1 piece on each of 10 plates. Place a scoop of ice cream on top of each cookie. Top the ice cream with the remaining cookies. Drizzle with the chocolate sauce and serve.
Yield: 10 servings