to a boil, stirring occasionally, then pour into a measuring cup with a spout and set aside to cool to 115 f.
pour the flour into the bowl of a stand mixer, adding the salt and yeast on opposite sides of the bowl. stir in each one with your finger, then blend in the caster sugar, mixed spice, orange zest, and butter with the paddle attachment.
dump the egg and half of the milk into the flour mixture, mixing on low speed. gradually add more milk as needed to bring the mixture into a soft, sticky dough; you may not need all the milk. keep the mixer going until all the flour 