Pastry cream:
Boil the milk in a small saucepan, split the vanilla pod in 2, seed it and put the seeds and the pod in the milk. Bring to a boil, keeping an eye on it.
In a mixing bowl, pour the egg yolks and add the sugar. whisk to make it whiten slightly and then add the cornflour and whisk;
When the milk is boiling, pour it over the egg mixture and whisk.
Return everything to the saucepan and cook until the cream thickens, whisking constantly; As soon as it starts to boil, turn off the heat and remove it to a mixing bowl. Cut the butter into pieces on top and stir in with a spatula.
Take the dough out of the fridge and lightly flour your work surface and the surface of the dough.
Roll it out into a rectangle +/- 60 cm long and 45 cm wide.
Whip the cream until it is smooth and spread it over the dough, leaving an empty edge in one of the lengths. Fill generously with chocolate
chips Roll the rectangle of dough loosely. Brush the edge where you are going to weld with water and close the roller tightly.
With a large sharp knife, cut 3 cm wide sections and place them on 2 baking sheets, 10 per tray and leave on for 2 to 3 hours at temperature (I leave them for 3 hours)
Preheat your oven to 210°c
Brush the rolls with beaten egg, you can add sprinkles on the rolls at the level of the hollows on the cream.
Bake for 17 to 18 minutes, keeping an eye on the coloring, once they are golden enough for your liking