Grecian urge: real Greek cooking

8 chicken thighs
50g butter
2 tbsp oil
2 red onions, peeled and finely chopped
2 bay leaves
1 dsp fresh thyme leaves
200ml milk
2 egg yolks
pinch of nutmeg
150g walnuts, crushed in a mortar
sea salt and freshly ground black pepper

1. Season the chicken thighs with salt and pepper.
2. Take a heavy-bottomed pan and heat the butter and the oil together. When hot but not smoking, add the chopped onions and sauté for 3 or 4 minutes until golden. Reserve in a bowl.
3. Add the chicken thighs to the pan and cook until they too have taken on a golden brown colour. Return the onions to the pan and add the bay leaves and the thyme leaves. Add enough water to barely cover the chicken.
4. Cover the pan and leave to simmer for 30-40 minutes, or until the chicken is cooked.Remove the chicken with a straining spoon and keep warm.
5. Strain the cooking liquid into a smaller saucepan and bring to the boil, then reduce it until you have about 800ml.
6. Whisk the milk and egg yolks together in a bowl. Turn down the heat under the sauce and pour the egg mixture into the sauce. Stir continuously until the sauce has thickened and be careful not to let it boil. Add the nutmeg and finally the crushed walnuts. Adjust the seasoning.
7. Leave it to simmer for 2-3 minutes to allow the flavours to combine and then pour the sauce over the chicken and serve.