Combine the milk, sugar and yeast in the bowl of a stand mixer. Allow to stand for 5 minutes until frothy.
Add the flour and salt to the yeast mixture. Start kneading with the dough hook then add the egg and butter.
Knead for 5 minutes until the dough starts coming away from the side of the bowl. (If the dough is too sticky, add 1-2tbsp) flour.
Cover the bowl with plastic wrap and place in the fridge to rise overnight. If you want to make the buns immediately, allow to rise for 1 hour at room temperature.
Remove the dough from the fridge and allow to come to room temperature.
To make the syrup, combine all the syrup ingredients (except for the butter) in a saucepan and allow to simmer for 10-15 minutes until the syrup is the consistency of maple syrup. Add the butter and mix well then remove from the heat.
When the dough has come up to room temperature, roll it out on a floured surface into a large rectangle of approximately 1cm thick.
Spread the butter over the dough then mix together the sugar and ground cinnamon and sprinkle over the top. Top with the chopped pecan nuts.
Roll the dough up tightly then cut into 4-5cm thick buns.
Pour half of the syrup in the bottom of an oven-proof casserole dish.
Place the buns on top of the syrup, allowing a little room in between them for the second proving stage.
Cover the buns with a piece of plastic wrap then allow to rise for 30 minutes while you preheat the oven to 180°C/350°F.
Before placing in the oven, pour the remaining syrup over the top of the buns (re-heat if necessary) then place in the oven.
Bake for 20-30 minutes until the buns are golden brown and cooked through.
Remove from the oven and allow to cool slightly before serving.