1. To make the cheese sauce, place the onion, bay leaf and milk in a small saucepan and bring to the boil. (Watch it carefully as it can easily boil over.) Remove from the heat.

2. Heat the butter and flour in another small saucepan, stirring constantly with a wooden spoon or whisk until it starts to foam. Add the milk (discarding the onion and bay leaf) gradually, stirring constantly to remove any lumps. Continue to cook for about five minutes, stirring until a thick sauce is produced. Remove from the heat, add a pinch of nutmeg and stir through the grated cheese. Season to taste.

3. Heat your overhead grill to very hot. In ramekins or a casserole dish spread the bolognese sauce over the base of the dish. Mix the pasta through the warm cheese sauce and pour over the base. Scatter the top of the pasta with more cheese and grill for 10 minutes until the cheese is browned.

3. Rest the macaroni cheese for five minutes before serving with a simple salad.

•   More recipes to use up leftovers including stale bread, excess fruit, sour milk, leftover meat, pasta and rice here