Preheat oven to 350°F. Set out an 8- or 9-inch-square glass or ceramic baking dish or into 8 individual 4-ounce custard cups.
In a heavy saucepan, combine 1/2 water and 1 cup of sugar. Stir over cup medium heat until sugar has dissolved and syrup is golden brown. Pour syrup either into baking dish or custard cups, evenly coating bottom(s). Place the baking dish or cups in a deep-sided baking pan or small roasting pan large enough to hold them without touching. Set aside.
In a heatproof bowl, dissolve chocolate or cocoa powder in hot water and set aside.
In a blender or in a bowl with a whisk, beat together eggs, milk, vanilla, salt, and one-cup sugar. Stir in dissolved chocolate mixture and 1/4 cup of the coffee liqueur. Pour mixture into baking dish or cups. Fill the larger baking pan or roasting pan with water to come 1 inch up Side Dish of baking dish or cups. Bake for 1 hour or until knife inserted into center of flan comes out fairly clean. Remove mold or cups from water bath and allow cooling.
To un-mold flan(s), run tip of wet knife along inside edge of dish. Place large serving dish over baking dish (or individual dessert plates over cups) and quickly invert.
Drizzle flan(s) with remaining 1/4 cup coffee liqueur. Garnish with whipped cream and shaved or grated chocolate.