Place the ramekins in a baking pan that has 3-inch sides.
Pour cream in a heavy saucepan and heat to simmering. Add expresso and broken chocolate. Whisk and watch closely. Do not overcook. Remove from heat. Add milk; stir.
In a small bowl, combine the juice of one orange. Add vanilla, sugar, and egg yolks; whisk until well incorporated.
Temper the egg mixture with cream mixture, then stir tempered eggs into cream mixture. Whisk until everything is completely combined and smooth.
Pour the custard into 6 ramekins in a water bath.
Bake 30 to 35 minutes in a 325-degree oven. Custards will be set around the edges and soft in the center.
Cool completely, then refrigerate, uncovered until cold.
*If you wish to brulee top, sprinkle sugar evenly over top. (It may help to pick up ramekin and swirl to evenly distribute sugar) Heat with a kitchen torch until caramelized.