"I wanted a break from the typical magic cookie bar and needed to use up some chocolate grahams and thought all of these flavors would work well together and I had all of the ingredients. It was youth group tested and approved!"
Mix chocolate graham cracker crumbs and butter together in a small bowl. Press into a 9x13-inch baking pan. Sprinkle walnuts evenly on top. Top with dark chocolate chips, white chocolate chips, and coconut.
Drizzle sweetened condensed milk evenly over coconut layer. Drop spoonfuls of raspberry preserves on top so there will be some on each bar once baked and cut.
Bake in the preheated oven until lightly golden, 20 to 30 minutes. Let cool until set, about 1 hour. Cut into 6 columns and 3 rows to make 18 bars.