Bon Appétit! The Cake

Aug 2, 2019  | 2 min  | 2019

American composer Lee Hoiby’s opera Bon Appétit! is based on a PBS television cooking lesson by Julia Child as she prepares Le Gateau au Chocolate l’Eminence Brune (a chocolate cake). Developed by Julia Child, discover what makes this cake recipe distinctive and sweeten the experience by making the cake yourself!

Le Gateau au Chocolat 'Eminence Brune'
Adapted from Julia Child's Kitchen, Alfred Knopf, 1975


  • 2 teaspoons instant espresso
  • 1/4 cup boiling water
  • 7 ounces semisweet chocolate
  • 2 ounces unsweetened chocolate
  • 4 large eggs, separated
  • 1 cup extra fine sugar plus 2 tablespoons
  • 4 ounces soft unsalted butter
  • 1/4 teaspoon cream of tartar
  • Pinch of salt
  • 3/4 cup cornstarch
  • Filling and frosting (see recipe below).


  1. Preheat oven to 325 degrees. Butter two 8-inch cake pans; place parchment paper in bottom of each, and then spray.
  2. Blend coffee and water in top of double boiler over simmering water. Remove from heat. Add chocolates; cover and set aside to melt.
  3. Beat yolks and gradually add 1 cup sugar. Continue beating until yolks are thick, pale yellow.
  4. Beat melted chocolate until smooth. Beat in butter, 2 tablespoons at a time; gradually beat chocolate and butter into yolk mixture.
  5. Beat whites until foamy; beat in cream of tartar and salt. Continue beating until whites form soft peaks; gradually beat in 2 tablespoons of sugar and beat until whites form stiff, shiny peaks. Sift on 1/4 of cornstarch and scoop on 1/4 of whites; stir with spatula. Scoop rest of whites on top; sift on 2 of remaining cornstarch and fold. Sift half of remaining cornstarch on top and fold in; sift on remaining cornstarch and fold to blend.
  6. Spoon batter into pans and smooth. Bang once on work surface to settle batter, and then bake for 15 minutes. A cake tester inserted near the edges should come out clean. Cool pans on racks. Wrap and chill for an hour before unmolding.


Chocolate Filling and Glaze

  • 4 ounces semisweet chocolate
  • 1 ounce unsweetened chocolate
  • 1 teaspoon instant espresso
  • 2 tablespoons boiling water
  • 2 ounces unsalted butter.


  1. Melt chocolates with coffee and water; beat in butter. If mixture is too liquid to spread, beat over cold water until lightly thickened.
  2. Unmold one layer of cake onto serving plate and spread top with 1/4 inch of icing. Unmold second layer on top of first and cover top and sides with remaining frosting.
  3. Serve, refrigerate or freeze. Return to room temperature before serving.

Yield: 16 servings.