1. Preheat oven to 350°. Line bottom and sides of an 8-inch square metal baking pan with parchment paper; cut off excess parchment paper around top edge of pan.
2. Place crumbs in a medium bowl. Drizzle with butter and 1 tablespoon water; toss with a fork until moist. Gently pat mixture into an even layer in prepared pan (do not press firmly). Sprinkle chips and morsels over crumb mixture. Top evenly with coconut and pecans. Drizzle milk evenly over top. Bake at 350° for 25 minutes or until lightly browned and bubbly around edges. Cool completely in pan on a wire rack.
Baking 101 Tip The bars can create a sticky mess in the pan, so it's crucial to line it with parchment paper. Because the milk needs to seep into the graham cracker crumbs, don't pack the crumbs too tightly in the bottom of the pan.