chicken lasagen

Preheat the oven to gas 6, 200°C, fan 180°C. Heat the oil in a frying pan. Add the chicken and brown. Set aside in a bowl. Add the onion and garlic to the pan; cook for 5 mins, or until softened. Stir in the oregano, chilli, tomato purée and tomatoes, then return the chicken with any juices; season. Bring to the boil, then simmer for 5 mins. For the sauce, melt the butter in a pan, then stir in the flour; cook for 1 min. Gradually add the milk. Bring to the boil, then simmer, stirring, for 5 mins. Remove from the heat. Stir in 60g cheese and the mustard; season. Spoon half the chicken mixture into a small baking dish. Top with 2 lasagne sheets, then the remaining chicken. Top with the last 2 lasagne sheets. Pour over the sauce and scatter over the remaining cheese. Bake for 20 mins, or until golden.