Preheat oven to 325 degrees F.
In a large saucepan milk, butter, chocolate, espresso powder and cinnamon over moderately low heat, whisking, until butter and chocolate melt and mixture is smooth. In a bowl whisk together the eggs, sugar, vanilla and salt. Whisk in the bread crumbs and pour in the hot milk in a stream, whisking constantly. Pour the mixture into a buttered 6-cup baking dish and bake for 45 minutes, or until pudding is set in the middle and a tester comes out clean. Allow the pudding to cool for 15 minutes and serve warm garnished with whipped cream and chocolate shavings.
Adapted from a recipe by Richard Sax for Gourmet Magazine