

Prepare the dough: Sift together the cocoa powder, flour and salt in a large bowl.
Using a mixer, cream the butter and sugar. Add the eggs one at a time, then the vanilla, incorporating each ingredient before adding the next. Add the dry ingredients and mix just until incorporated, scraping the bottom of the bowl with a rubber spatula.
Using a 2-inch round cutter, cut the dough into 64 circles. (You can reroll the scraps once.) Place the cookies about 2 inches apart on ungreased baking sheets and chill for 20 minutes. Preheat the oven to 325.
Bake the cookies until they are set and slightly darker around the edges, about 20 minutes. Cool completely on wire racks.
Meanwhile, prepare the filling: Using a mixer, cream the butter and shortening until fluffy. Beat in the confectioners' sugar and vanilla.
Flip half of the cookies upside down and top each with 1 level tablespoon of filling. Press the remaining cookies on top to make sandwiches.
Preheat oven to 325 degrees F.
Roughly chop the walnuts and then gently toast in a dry skillet over medium heat until they brown and are slightly fragrant. Season walnuts with salt once they are finished toasting. Add the walnuts, mayonnaise, mustard, lemon juice, celery, olive oil, and salt and pepper, to taste, in a large mixing bowl and combine. Fold in the shredded chicken and set aside while you prepare the bread.
Toast the bread in a hot oven until golden. Smear each piece with a little butter and then a tablespoon of cranberry sauce over 4 of the pieces. Lay the 4 cranberry-smeared pieces out on a sheet tray and top each piece with 2 to 3 slices of thick-cut brie. Pop this back in the oven for a minute or 2 so the cheese is slightly melted and creamy. Remove from the oven and top with a few slices of green apple. Top with a scoop of the chicken salad and cover with the other half of the bread to complete the sandwich. Serve.