For the dough, melt the butter, beat the egg and juice the orange, then mix all the dough ingredients (except the milk) in a bowl, adding up to 75ml of milk little by little, until the mixture forms a smooth and relatively stiff dough.
Let it rest for 15 minutes while you preheat the oven to 185ºC/gas 4½, then roll the dough out into a very long, thin rectangle, about ½cm thick, 50 to 60cm long and 10cm wide.
For the filling, mix the sugar and spices together and sprinkle over the dough. Melt and drizzle the butter over, and make into a roll, rolling up from one short end to the other.
Divide the dough up into 4 slices and place on a parchment-lined baking tray.
Combine the glaze ingredients in a small pan over a medium heat and bring to the boil.
Spoon a little glaze over the dough and bake for about 40 minutes, basting with more glaze a couple of times, until golden, risen and sticky. Your folar may spread a little, but will still be delicious.