Preheat oven to 425°F. Generously butter 4 (6-oz.) ramekins. Place the ramekins on a baking sheet.
Microwave the chocolate and butter in large microwavable bowl on high in 30 second increments until butter is melted, stirring in between.
Stir until the chocolate is completely melted. Stir in the Grand Marnier and vanilla. Set the chocolate mixture aside.
Whisk the eggs and yolks with the granulated sugar until the eggs are tripled in volume and leave a ribbon when drizzled over the surface. Sift the flour, cinnamon and pepper over the eggs and use a wire whisk to fold them in. Fold 1/2 of the egg mixture into the chocolate then fold in the remaining eggs. Divide the batter evenly between the prepared ramekins. *See Note
Bake 10-12 minutes until sides are firm but centers are still soft. Remove from the oven and let stand 1 minute. Carefully loosen edges with small knife. Invert cakes onto serving plates. Sprinkle with confectioners’ sugar. Serve immediately.
Notes
*At this point the ramekins can be refrigerated for several hours or frozen for a few days. Allow the refrigerated or frozen cakes to come to room temperature while the oven preheats. You may need to add a few minutes to the baking time.