Chop the onion

Heat the butter in a pan

Add the onion and sprinkle with sugar

Cook for 10/15 mins or until the onion is soft/ caramelised

Sprinkle flour over onions

Stir and cook for 1 min

Gradually stir in stock

Bring mixture to a boil and then reduce the heat and leave to simmer gently until gravy thickens.