Sift the bread flour, caster sugar and salt together in a bowl then mix in the yeast.
Gradually add the milk and warm water and combine to achieve a pliable dough.
Lightly flour a work surface then tip out the dough and knead for 5-6 minutes until smooth and elastic.
Mix the peel, orange zest, sultanas and ground cinnamon into the dough until well distributed. Then leave to rise in the bowl for an hour.
Line a large baking tray with greaseproof paper and divide the dough into 85g pieces then shape them into balls.
Place the balls onto the baking tray evenly spaced apart and allow to prove for another hour.
Preheat the oven to 230°C / 450°F / Gas mark 8.
Make the flour piping by combining the plain flour, caster sugar and 80ml of water and blend until smooth.
Transfer to a piping bag and with a small plain nozzle and pipe a cross over the top of the buns when they are ready for the oven.
Bake for 15 minutes then turn the oven down to 200°C / 400°F / Gas mark 6 and cover with foil then bake for a further 10 minutes.
Heat two tablespoons of water and sugar until all of the sugar is dissolved.
Brush over the buns just after removing them from the oven.
Allow to cool for 10-15 minutes and serve warm.