Preheat the oven to 425 degrees. In a small saucepan, melt the chocolate with 1/2 cup cream, stirring until smooth, about 2 minutes. Pour into a large metal bowl. Whisk in the remaining 1 cup cream, the kirsch and vanilla. Refrigerate the mixture for 30 minutes.
Meanwhile, place the puff pastry shells on a parchment-lined baking sheet; brush with the egg white and sprinkle generously with the raw sugar. Bake until puffed and golden, about 15 minutes; let cool for 5 minutes. Using a small, sharp knife or a fork, pry off the lids from the top of the warm pastry shells. Scoop out and discard any soft dough from the inside. (Can be made up to 3 hours ahead. Let stand, uncovered, at room temperature until ready to fill and to serve.)
In a medium skillet, combine the cranberries, brown sugar and 1 cup water. Bring to a simmer and cook until the berries burst and the mixture thickens, 2 to 3 minutes. Let cool for 15 minutes, then transfer to a small serving bowl or pitcher.
Meanwhile, using a handheld electric mixer, beat the cold chocolate mixture on medium-high speed until thick and billowy, about 1 minute. Spoon the chocolate cream into the pastry shells; place the lids on top. Serve with the cranberry compote.