Mexican Coffee Bun (Rotiboy)

In a mixer bowl, add all the dry dough ingredients — bread flour, castor sugar, salt, milk powder and yeast — and mix thoroughly.

Mix the water and 1 egg together, then gradually add to the dry ingredients while kneading on medium speed with a dough hook for about 10 minutes.

Slowly add the 2 oz butter and keep kneading until the dough is shiny and elastic and stretches without breaking.

Cover the dough with a cloth and let it proof for about 40 minutes, until doubled in size.

Meanwhile make the topping: beat the 7 oz butter and powdered sugar together until pale in color.

Gradually add the 3 beaten eggs to the topping, mixing well after each addition.

Fold in the cake flour on low speed.

Mix the instant coffee with 2 tbsp hot water, then add it and the coffee liqueur to the topping. Mix until combined and set aside.

Punch the proofed dough down on a lightly floured surface to release the air.

Divide the dough into 45 g (1.5 oz) portions and roll each into a small circle.

Place 1 teaspoon of the chilled filling butter in the center of each circle, wrap the dough around it and shape into a bun. (Keeping the butter cold and using just a teaspoon stops it leaking while baking.)

Leave the shaped buns to proof for about 45 minutes, until doubled in size.

Spoon the coffee topping into a piping bag and pipe it in a spiral around each bun, just before baking so it doesn't melt too early.

Bake at 215°C (419°F) for about 18 minutes. Check after 15 minutes and cover with foil if the buns are browning too fast.