For the pastry cream:
1 cup milk
6 eggs, separated, at room temperature
2/3 cup sugar
3 Tbs. all-purpose flour
2 tsp. finely grated orange zest
Pinch of salt
1/4 cup Grand Marnier or other orange liqueur
1 tsp. vanilla extract
Crème anglaise for serving

To make the pastry cream, in a saucepan over medium heat, warm the milk until
small bubbles appear along the edge of the pan. Remove from the heat.
In a bowl, whisk together the egg yolks, 1/3 cup of the sugar, the flour,
orange zest and salt until pale and well blended. While whisking, slowly add
the hot milk.
Pour the mixture back into the saucepan and place over medium-low heat. Cook,
whisking constantly, until the mixture comes to a boil. Continue to cook,
whisking constantly, for 1 minute. Remove from the heat and whisk in the
liqueur and vanilla.
Pour the pastry cream into a large bowl and gently press a piece of plastic
wrap directly onto the surface to prevent a skin from forming. Let cool to room
temperature or refrigerate until ready to bake.
Preheat an oven to 375°F. Lightly butter a 6-cup soufflé dish and dust with
sugar.
Remove the plastic wrap from the pastry cream and whisk until smooth. In a
deep, spotlessly clean bowl, using an electric mixer, beat the egg whites on
medium-high speed until they are foamy and soft peaks form when the beaters are
lifted. While beating, gradually add the remaining 1/3 cup sugar and continue
to beat until stiff peaks form. Scoop about one-fourth of the egg whites onto
the pastry cream and, using a rubber spatula, fold in gently to lighten the
mixture. Then fold in the remaining whites just until no white streaks remain.
Scoop into the prepared dish. Run a thumb around the inside rim of the dish to
keep the batter from sticking and help the soufflé rise.

Bake until the soufflé is puffed and the top is browned, but the soufflé
still jiggles slightly when the dish is gently shaken, about 30 minutes. Serve
immediately with the crème anglaise. Serves 6 to 8.