Preheat the oven to 400 degrees F.

In a small saucepan melt the butter. Add the flour and whisk to blend. In another pan bring milk just to a boil, and then whisk the milk into flour and butter mix, add the salt and vanilla. Allow the milk to cool. In a bowl over simmering water melt the chocolate, sugar, and Grand Marnier, add the egg yolks, 1 at a time, whisking well to incorporate after each addition. Stir in the milk mixture. Whip the egg whites to stiff peaks, and fold them into the chocolate mix. Put the souffle mix into ramekins or souffle cups that have been buttered and sugared. Bake 12 to 16 minutes or until puffed and browned.