2 ¼cupsmilk(Or a plant based milk like coconut or almond)
2tbspbutter, softened(Or vegan butter)
Add the milk and vanilla into a saucepan. Heat the milk over medium high heat and bring it to a boil.
While the milk is being heated, place the sugar, egg and yolks, cornstarch, cocoa powder and salt in a bowl. Whisk until you have a thick, smooth mix. Place this egg mix on a towel or napkin (to prevent it from slipping), and then set it aside until the milk comes to a boil.
As soon as the milk starts to boil, remove it from the heat. Slowly pour about one half of the hot milk in a thin stream, into the egg mix, WHILE WHISKING CONSTANTLY to temper the egg mix. When the eggs have been tempered, add the egg mix back into the hot milk in the saucepan.
Heat the custard base, over medium heat, while whisking vigorously until it starts to thicken - this should take about 2 - 5 minutes (depending on the heat level).
While whisking, let the custard release some bubbles (come to a boil gently). When the first bubbles break the surface, lower the heat to low and immediately add the bittersweet chocolate chips. Whisk until the chocolate is completely melted.
Remove from the heat and add the butter. Whisk in the butter, until that too is completely mixed into the custard.
Pour the custard into a bowl and immediately cover the surface with plastic wrap, making sure the plastic wrap is touching the whole surface. This is to prevent a custard skin from forming on top.
Let the custard cool down to room temperature and then let it chill in the fridge for a few hours, until it’s completely chilled.
Use as needed after the chocolate pastry cream has been chilled. You may need to whisk the pastry cream to make it smooth again before use.
For a richer creme patissiere, you can substitute the whole egg with 3 egg yolks (6 egg yolks in total).
For a thicker consistency add only 2 US cups (480 mL) milk. This consitency is even thicker and is good for piping shapes that are stiffer than this recipe.
Mocha Pastry Cream - Instead of the vanilla (or in addition to the vanilla) - add ½ tsp of instant coffee granules. Allow the instant coffee to dissolve in the milk and then proceed with the recipe.
Bourbon Chocolate Pastry Cream - Use ¼ cup less of the milk/half and half for the custard. Add 3 tbsp of bourbon along with the butter and whisk it in until well mixed with the custard.
Jaffa Pastry Cream - Add 1 tsp orange extract along with the vanilla extract and then proceed with the recipe.
Cinnamon Chocolate Pastry Cream - Add ½ tsp cinnamon along with the vanilla into the milk and then proceed with the recipe.