First Layer:

1. Line a 11″x7″ baking dish with parchment paper, using a piece of parchment paper about 16 inches long and 7 inches wide. Let the extra paper lay over the sides of the dish to create a mock-sling so the bars can be lifted out of the pan when ready to cut.
2. In a large bowl, combine all 1st Layer ingredients, butter, brown sugar, cocoa powder, egg whites, graham crackers, coconut and walnuts, together stirring with a spoon until all are evenly mixed.
3. Press firmly into the bottom of the lined baking dish. Place in the freezer for 20-30 minutes and begin preparing second layer ingredients.

Second Layer:

1. In a large bowl with a whisk, or a stand mixer with a whisking attachment, beat together powdered sugar, butter, heavy cream, vanilla and custard powder until light colored and airy. It will remain fairly stiff, but spreadable.
2. Remove bars from the freezer, spread the custard over the top of the first layer with an offset spatula. Spread out evenly and place bars back into the freezer until the third layer is ready to finish.

Third Layer:

1. In a small sauce pan, fill with 1″ of water and bring to a simmer. Set a large heat safe bowl over the top of the pan adding the butter and chocolate to the bowl.
2. Stir together until the butter and chocolate chips have just melted and mixed together. Remove from heat as soon as they have melted to ensure they don’t scorch.
3. Promptly pour over chilled layer of custard. Smooth out with an offset spatula and place back into the fridge until the chocolate has set.

To Cut and Serve:

1. Slide a sharp knife around the edge of the pan to ensure none of the custard or ganache has stuck to the sides of the baking dish.
2. Grasp the two over hanging edges of the parchment paper and lift the bars out of the baking dish.
3. Using a sharp knife cut the bars into 24 even squares. Serve immediately or chill. Can be refrigerated up to three days.