Place the 1 1/2 cups roughly diced California Prunes in a small saucepan with the bourbon and water. You may use all the bourbon or all water. Bring to boil and then reduce to simmer for 5 min.

Preheat oven to 325F. Prepare a 9" cake pan by buttering and then placing a round piece of parchment on the bottom of the baking pan. To get the size of the bottom of the pan easily just place the pan on the center of a parchment sheet and outline the bottom of the pan and then cut it out just inside the line. This should now fit easily in your pan.

Place the chopped chocolate and diced butter in a heatproof bowl over a pot of simmering water. Make sure the bottom of the bowl is not in the water. Stir until melted and smooth. Remove from heat and set aside.

Sift together the flour and cocoa and set aside.

Using a standup mixer with a paddle attachment beat the egg yolks with the vanilla and sugar. Add in the melted chocolate and stir. Add in the flour and cocoa and stir until combined. Fold in the prune mixture.

In another clean bowl beat the egg whites until soft peaks form. Fold into the batter in two batches and fold until just mixed. Pour into prepared cake pan and bake for 35-40 minutes.

When the center of the cake feels firm and spring back slightly with a light touch the cake is done. Let cool completely in the pan.

Invert onto a serving dish keeping cake bottom side up. Dust with cocoa powder.

Melt the butter in a saucepan over medium heat. Add the brown sugar and cook until dissolved. Slowly pour in the whipping cream and continue to cook, whisking, until the sauce thickens slightly. Remove from heat and whisk in the bourbon if using. Add the quartered prunes. Serve warm with the chocolate cake.