In the bowl of a stand mixer, place the yeast, caster sugar and the milk, stir to combine, and set aside for 5 minutes. The mixture will start to foam when the yeast is active.

Once the yeast mixture is ready, add the plain flour, mixed spice, cinnamon, butter and egg to the yeast mixture. Use the dough hook of the stand mixer to knead the dough for 5 minutes on medium. 

Turn the stand mixer off and add the sultanas and chocolate chunks. Beat on medium for another 3-5 minutes or until the dough is elastic. 

Once the dough has risen, line a square baking tin with baking paper. Separate the dough into 12 even balls, rolling using your hands and placing side by side in the tin. You don’t need much room between them as they will easily pull apart after cooking. Cover with the damp cloth and let rest in a warm place for another 30 minutes.

Meanwhile, preheat the oven to 200C (400F). To make the crosses, mix the plain flour and water in a small bowl until combined. Either use a piping bag if you want neat crosses, but if not, you can decorate using a knife as long as your mixture is nice and thick. 

Once the buns have had time to rise a little more, either pipe or use a knife to pull the cross mixture across the buns to form crosses on to the top of the hot cross buns. I found using a knife wasn't too hard but you just had to load it up with the cross mixture first. 

Once you have piped all the hot cross buns, place them in the oven. Bake for 25-30 minutes or until golden and springy to touch.

Right before the hot cross buns are ready, place the sugar and water in a small saucepan over a medium heat. Stir until the sugar has dissolved and and the mixture is simmering.