Crème Pâtissière with Grand Marnier

Instructions

1. 1. Beat the egg yolks, sugar, vanilla, and citrus zest.
2. 2. Whisk in the flour with a spoon, mixing from the center.
3. 3. Heat the milk just before boiling.
4. 4. Temper the yolks with a small quantity of warm milk to avoid cooking them too soon.
5. 5. Put the whole mixture back into the casserole, stirring constantly until thick and boiling.
6. 6. Add the Grand Marnier and cook one minute more to eliminate the alcohol.
7. 7. When ready, cover with plastic film to avoid skin forming, or transfer to piping bag.