Preheat the oven to 350 degrees. Prepare two coffee mugs or other oven-safe vessels by spraying them with cooking spray, and set them aside.
In a bowl, combine the eggs, milk, sugar and vanilla and whip with a fork until everything is well combined. Mix in the bread, making sure it is all evenly coated. Stir in the chocolate and pecans, and bake for 25 minutes.
Remove from the oven and carefully serve while still warm—using a potholder or towel, since the handle and vessel will be hot.