Place the milk and butter in a small saucepan and heat over a low heat until the butter is just melted.
In a roomy mixing bowl, mix together the flour, salt, mixed spice, ground cinnamon, ground nutmeg, lemon zest, dried yeast and sugar.
Stir in the beaten egg and warm milk.
Mix to make a soft dough then knead for 7 minutes by hand or 5 minutes in a stand mixer until smooth and elastic. (If making in a bread machine, see note below)
Place in a clean bowl, cover with a clean tea towel and leave in a warm place for 1-1½ hours, until the dough has doubled in size.
Tip the dough out onto a lightly floured board and roll out to a rectangle size 20cm x 30cm (8" x 11")
Mix 25g softened butter with the lemon zest and spread this in an even layer over the dough, then sprinkle over the sultanas.
Mix the brown sugar with cinnamon and mixed spice and then sprinkle this in an even layer over the sultanas.
Press down the long side closest to you on the board. Take the opposite long edge and roll tightly towards you.
Cut the roll into 9 even sized pieces - around 4-5cm thick (1.5-1.8")
Line the bottom (not the sides) of a 20cm x 20cm(8" x 8") square tin with baking paper and place the scrolls, cut facing up, into it, leaving an even gap between them all.
Cover with a tea towel and leave in a warm place for 30-40 minutes until the scrolls have grown and are now touching.
Preheat the oven to 180˚C fan/ 200˚C / 356˚F Convection / 392˚F
Place the scrolls into the oven and bake for 20-25 minutes, checking after 15 minutes - if the scrolls are starting to brown and the sultanas are catching then cover with foil.
Once baked, leave to cool in the tray for 5 minutes before topping with the glaze.