Preheat oven to 325°F. Beat sugar and yolks until light and fluffy. Beat in butter until combined. Beat in flour to make a stiff dough. Pat dough into an 8-inch square on a baking sheet. Bake 25 to 30 minutes until edges are golden brown. Cool 10 minutes. While warm cut four rounds with a cutter the same diameter or slightly larger than the ramekin. Let cool completely. Shortbread scraps can be used for Raspberry Key Lime Pie crumb crust.

Line bottom and sides of four 4-ounce size ramekins (3" diameter by 1-1/2" deep) with plastic wrap, allowing 1 1/2-inches to overhang on sides. Reserve 1/4 cup each berry for garnish. Place remaining berries, sugar and Crème de Cassis in a medium saucepan. Bring to a simmer over medium heat; cook 5 minutes or until berries soften and break down. Press firmly through a sieve to drain juices. Discard solids. Cool juice to room temperature.

Cut centers of bread slices with a biscuit cutter the diameter of the ramekins. Or, invert a ramekin on bread and cut around edges with the tip of a knife.

Dip bread slices briefly in berry juice, one by one, to nearly saturate. Stack four slices in each ramekin. Reserve any remaining juice for garnish.
Fold plastic over tops of ramekins. Place ramekins on a dinner plate and invert another plate over ramekins. Place a heavy food can on top to weigh down. Refrigerate 6 hours or overnight (can be made up to 48 hours before serving).
Open plastic wrap and invert each pudding onto a shortbread cookie. Lightly sift cocoa powder onto each serving plate. Place pudding on plate, top with a dollop of whipped cream and garnish with reserved juice and berries. Serve with a small scoop of vanilla ice cream and cookie on the side.