Cook the macaroni in plenty of boiling water, until just cooked, then drain well, add 1-2 tsp of extra virgin olive oil to stop the pasta sticking together

Add oil in a separate large pan, add the onion and cook for 5 minutes to soften

Add the milk, stock cube then bring to the boil

Meanwhile mix the butter and flour together, to form a paste texture

Once the milk is boiling, turn down the heat to a simmer, then mix in the butter and flour paste, and cook gently for 2 minutes

Take off the heat and stir in 125g of the cheese and the cooked macaroni

Add a pinch of nutmeg, mustard, pepper, salt.

Oven some bread untill its hard and crunch over the set maceroni

Spoon into an ovenproof dish, add the rest of the grated cheese (50g).

Then brown under a hot grill or in the oven for 6-10 minutes