1) Preheat the oven to 350°F. Grease a 9" square pan.
2) In a medium-sized mixing bowl, combine the graham cracker crumbs, confectioner's sugar, and 6 tablespoons of the melted butter. Press the mixture into the bottom of the pan. Set aside.
3) With a hand or stand mixer, beat together the remaining 4 tablespoons melted butter, the boiling water, sugar, vanilla, and dried whole milk until thick and smooth. Pour into the pan.
4) Top with the semisweet chocolate chunks, white chocolate chips or chunks, nuts, and coconut.
5) Bake the bars for 24 to 26 minutes, until the coconut starts to turn golden. Remove them from the oven.
6) Combine the caramel with the tablespoon of milk or cream, and heat until the caramel is pourable, stirring to combine.
7) Pour the caramel over the bars. Allow the bars to cool and set before cutting.
Yield: 16 bars.