Preheat oven to gas 4, 180ºC, fan 160ºC. Heat oil in a small saucepan. Add the onions and cook gently until soft, but not browned. When soft add brown sugar, mix together and heat through to allow sugar to caramelise the onions. Allow to cool slightly.
Roll out pastry and line 12 fairy cake patty tins with the pastry. Mix together the sausage meat and onions, and place a small spoonful of the mixture into each pastry case. Cut out 12 lids (re-roll if you need to), brush a little water on the edges of each lid and place damp edge down onto the mixture. Press to seal edges and decorate if you wish. Use a knife to make a small air hole in the top and brush with egg and milk glaze.
Place in a preheated oven and cook for about 15-20 minutes until risen and golden. These can also be made as tarts, just leave off the lids!
Serve warm or cold with a large seasonal salad.
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Haven't got time to cook this from scratch?
Try our ready-made version - Tesco Melton Mowbray Pork Pies.