Prep. time: 15 minutes
Cooking time: 10 minutes
Chilling time: 6 to 7 hours

1.  In a bowl, combine the 5 egg yolks with the cornstarch, sugar and vanilla sugar.
2. Heat the milk with the cinnamon and lemon zest.
3. When the mixture begins to simmer, whisk in the egg yolk mixture, beating well to prevent the formation of lumps.
4. When the custard has thickened, remove it from the heat and pour into a buttered rectangular dish. Cover.
5. Refrigerate for 6-7 hours. The mixture must be firm so that it can be cut.

Finishing

1. Unmold the custard and cut into approximtely 4 cm triangles.
2. Bread each triangle by dipping into (in order): flour, beaten egg, and bread crumbs.
3. Fry each triangle in hot oil, turning halfway so it is browned on both sides.
4. Drain on paper towels. Roll in sugar and sprinkle with cinnamon.