Preheat oven to 300 degrees F. Scrape inside of vanilla bean halves into cream and add the bean halves, sugar, and coffee in a sauce pan over medium heat. Bring the cream up to a boil and reduce to a simmer. Simmer the cream for 5 minutes. Remove from the heat and discard the vanilla bean. In an electric mixer, beat the yolks. Gradually pour the hot cream into the mixer. Mix until incorporated. Strain the liquid into a pitcher. Place eight (3/4 cup) in a roasting pan. Fill the pan with water, filling them up to the rim. Cover the pan loosely with foil and bake for 1 to 1 1/2 hours or until set. Remove from the pan and let the custards cool completely. Place in the refrigerator and chill for 1 hour. Garnish with whipped cream, chocolate shavings and espresso powder.