For the bread dough; combine the flour, sugar, salt, milk powder, and instant yeast in the bowl of a stand mixer fitted with a dough hook, or in a large bowl

Add the lukewarm milk and mix until a rough dough ball forms

Add the unsalted butter and knead for 10-15 minutes with the stand mixer, or approx 20 minutes by hand until smooth and elastic

Roll into a ball, place in a bowl and cover with cling wrap

Place the bowl in a warm spot to proof for 60-90 minutes, or until doubled in size

Once doubled in size remove the dough from the bowl and punch out any air

Divide the dough into 8 equal pieces

Flatten each piece and put a small square of butter (10g) in the center

Enclose the cubed butter by pinching the edges of the dough together and rolling it into a ball

Place the dough balls on a baking sheet lined with parchment paper and cover them with cling wrap

Place the tray in a warm spot to proof for 30-60 minutes, or until almost doubled in size

Meanwhile, preheat the oven to 180°C/355°F

To make the cookie topping, combine the instant coffee powder and hot water together in a small bowl, and set aside

Combine the softened butter and sugar in a large bowl and whisk until smooth

Add the egg and whisk until well combined

Add the slightly cooled coffee mixture and whisk until smooth

Sift in the flour and mix until just combined

Transfer the batter into a piping bag fitted with a small round nozzle

Uncover the proofed buns and pipe swirls of the coffee topping over the top of the buns

Then bake the buns for 15 minutes, or until cooked through

Remove from the oven and cool for 5 minutes, then enjoy warm!