BUN DOUGH

1. Place the lukewarm milk, 15g of the sugar, and the yeast in a medium sized bowl, and stir to combine. Leave for 10-15 minutes, or until foamy.
2. In the bowl of a stand mixer fitted with the dough hook attachment, place the remaining 105g sugar, flour, cocoa, salt, cardamom, and cinnamon.
3. Add the milk mixture and vanilla bean paste to the dry ingredients, and mix on low for 2-3 minutes. Increase the speed of the mixer to medium, and mix for a further 5 minutes. Add the butter a little at a time, waiting until it is incorporated until adding the next piece. Mix for a further 7-10 minutes, until the dough is smooth and soft.
4. Turn out the dough onto a work surface (I do not find that there is a need to flour, but add some if needed), and knead in the chocolate by hand. It will take longer than you expect but the chocolate will eventually incorporate into the dough.
5. Shape the dough into a ball, and place in a lightly oiled bowl. Cover with plastic wrap and place in a warm spot until doubled in size, 1 to 1 1/2 hours, or place in the fridge overnight. While the dough is proofing, make the pastry cream.

PASTRY CREAM

1. In a medium bowl, whisk together the corn starch and sugar. Add the eggs, salt, and vanilla bean paste, and whisk well to combine.
2. In a medium saucepan, whisk together the whole milk and cocoa powder, then place over a low heat until just shy of a simmer.
3. Whisking constantly, pour about half of the warm milk mixture into the egg mixture. Whisk until smooth, then add back into the saucepan. Whisking constantly, cook until thick. Add the butter and whisk to combine.
4. Transfer to a piping bag fitted with a round piping tip, and a clip just above the tip to prevent any leakage. Twist the piping bag closed, or secure with another clip, and store in the fridge until needed.

ASSEMBLY

1. Lightly grease an 11” x 13.5” baking pan or roasting dish. Turn the dough out onto a work surface, and weigh the dough. Divide the weight of the dough by 12, and divide the dough into 12 equal sized pieces. Roll each tightly into a ball, then arrange evenly in the pan.
2. Lightly cover the pan with plastic wrap, and leave in a warm place for about 45 minutes, or until puffy and the dough springs back when lightly pressed with a finger.
3. Preheat the oven to 350°f / 180°c. Using a sharp paring knife or razor blade, score crosses in the buns.
4. Bake the buns for 20 minutes, then remove from the oven and pipe the chocolate pastry cream in crosses in the holes provided by the scoring.
5. Return the buns to the oven and bake for a further 10 to 15 minutes, or until the buns are lightly golden brown (this can be a little hard to gauge with the cocoa in the dough), or until they register 200°f / 90°c on an instant read thermometer. While the buns are baking, prepare the sugar syrup.
6. Remove from the oven and leave to cool, before brushing on the sugar syrup (recipe below).

SUGAR SYRUP

1. Place all the ingredients in a small saucepan, and bring to a boil. Boil for 1-2 minutes, then leave to stand until ready to use.
2. Store leftover buns in an airtight container at room temperature. Reheat in the microwave briefly before eating. Serve with butter.