Warm the milk gently in a medium saucepan. Take off the heat and transfer ⅔ of the milk into a jug and set aside (you will need this to loosen the dough with later).
Crumble the fresh yeast into the pan and stir in the sugar and 3 tbsp flour. The mixture should be the consistency of double cream. Put a lid on the pan and leave on the kitchen counter to double i