Chocolate Spice-Cake Pudding

We created this intense "bread pudding" using chocolate spice cake instead of bread and baked it in a Charlotte mold with a custard adapted from a recipe in Maida Heatter's Book of Great Desserts (Random House, 1991).

Yield: serves 10

For the Cake

10 tbsp. butter
2 ¹⁄₂ cups all-purpose flour
2 tsp. baking soda
1 ¹⁄₂ tsp. ground ginger
¹⁄₂ tsp. salt
¹⁄₂ tsp. ground cloves
¹⁄₂ tsp. dry mustard
¹⁄₂ tsp. freshly ground black pepper
¹⁄₂ cup firmly packed dark brown sugar
2 eggs
1 cup dark or light molasses
1 cup strong coffee, cooled
2 oz. bittersweet chocolate, melted and cooled
1 tsp. ground cinnamon

For the Custard and Serving

2 oz. bittersweet chocolate, chopped
4 cups milk
1 cup heavy cream
6 eggs
2 tsp. vanilla extract
<a href="http://www.saveur.com/article/Recipes/Chocolate-Sauce">Chocolate Sauce</a>

Instructions

For the cake: Preheat oven to 375°. Grease a jelly roll pan with 1 tbsp. of the butter; set aside. Sift flour, baking soda, ginger, cinnamon, salt, cloves, mustard, and pepper together into a medium bowl. Beat sugar and remaining 9 tbsp. butter together in a large mixing bowl with an electric mixer on medium speed until light and fluffy. Beat in eggs, 1 at a time, then molasses. Mix in one-third of the flour mixture, then one-third of the coffee; repeat process twice. Beat in chocolate. Pour batter into prepared pan. Bake until top springs back when touched, about 15 minutes. Set aside to let cool.
For the custard: Melt chocolate with milk and cream in a heavy saucepan over medium-low heat. Set aside to let cool. Whisk eggs and vanilla together in a small bowl, whisk into milk mixture, and set aside.
Cut parchment paper to fit sides and bottom of a 13-cup charlotte mold. Grease mold with half the remaining butter, line with paper, and grease with remaining butter. Cut a circle of cake to fit bottom of mold and press into bottom. Cut 7 more pieces into flared "planks", about 1" × 2" × 3 1⁄2". Place in mold wide end up, leaving 3⁄4" spaces in between, as if making a crown. Cut remaining cake into irregular squares and place inside crown. Pour custard over cake pieces. Bake for 70 minutes. Remove from oven and let cool for 45–60 minutes.
To serve: Invert cake onto a plate and unmold. Pour half the Chocolate Sauce over cake and serve the remaining sauce on the side.