Add the flour, salt, yeast, and sugar into the bowl of a stand mixer and whisk briefly to combine.

Make a well in the centre and add the milk and egg.

With the dough hook attached, mix to form a shaggy dough.

Continue kneading on a low medium speed for about 10 minutes or until the dough is smooth and elastic and forms a ball around the dough hook.

Add the butter and continue kneading until the dough is smooth and elastic and is no longer sticking to the sides or bottom of the bowl.

Form the dough into a ball and place it in a large bowl. Cover with cling film, leave for 20 minutes, and then transfer to the fridge overnight.

To make the filling, add the chocolate, butter, and coffee powder into a heatproof bowl set over a pan of simmering water and melt together, stirring occasionally.

Take the bowl off the heat, add in the remaining ingredients, and stir to combine. Set aside.

Lightly grease an eighth sheet pan, a rimmed 23x15cm baking tray, and line the base with parchment paper.

Lightly flour the work surface and tip out the chilled brioche. Roll out into a rectangle about 25x40cm.

Spread over the liquid filling, taking it right to the edges.

Wait a few minutes until the filling goes from wet to tacky and then roll it up into a 25cm long log.

Cut the log into 6 equal slices and place them, cut side up, into the prepared tray.

Lightly cover with cling film and set aside until doubled in size, about an hour.

Just before the buns are ready to bake, preheat the oven to 190ºC (170ºC Fan).

Bake the buns for 30 minutes or until golden brown. Remove and set aside to cool slightly.

To make the glaze, add all of the ingredients into a large bowl and mix until smooth.

The consistency should be thick but still just about pourable.

Spoon the glaze onto the still slightly warm buns and spread over the surface.

If stored in a sealed container, the buns will keep for 2-3 days but they’re best enjoyed on the day they are baked.