Instructions: Heat the oven to 350 degrees. Butter a 9-inch-square baking pan.

Combine the chocolate and butter in the top of a double boiler set over, but not touching, simmering water and stir until melted and smooth. Remove from the heat and cool slightly.

Whisk the egg yolks with the sugar and whisk into the chocolate mixture. Whisk in the vanilla. In a clean bowl, beat the egg whites with salt just until soft peaks form. Carefully fold into the chocolate mixture. Pour into the prepared pan. Bake until set but not dry, 30 to 35 minutes. Cool slightly, then cut into squares.

For the Bitter Orange Sauce:Combine the cream and orange zest in a small saucepan and heat just until bubbles form around the perimeter. Remove from the heat and let stand 30 minutes.

Boil the orange juice until reduced to about 1 1/2 tablespoons and starting to caramelize. Blend into the cream.

Whisk together the egg yolks and sugar until the sugar dissolves. Reheat the cream to scalding, then pour about one-fourth into the egg yolks, whisking continuously.

Whisk the mixture back into the saucepan with the cream. Cook over low heat, stirring constantly, until the mixture thickens enough to coat the back of a spoon, about 5 minutes. Stir in the liqueur. Serve warm or chilled. (Makes 1 1/4 cups)

Serve cake with the Bitter Orange Sauce drizzled over top.

This recipe yields 8 servings.

Bitter Orange Sauce recipe adapted from "Desserts" by Nancy Silverton (Harper & Row, 1986). By Regina Schrambling.

NOTES : Bitter Orange Sauce portion of recipe adapted from "Desserts" by Nancy Silverton (Harper & Row, 1986)

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