Creamy Chicken & Mushroom Lasagne

Heat a drizzle of olive oil in a deep frying pan over medium-high heat. Fry the mushrooms for 2 minutes, then add the chicken mince and fry for 3 minutes, separating it as you do so. Add the onion, leek and garlic and fry for 3 - 4 minutes, then take the pan off the heat and set aside until step 4.

Melt a knob of butter in a saucepan over medium-high heat. Whisk in the flour, then pour in a third of the stock and whisk to incorporate (see Tip). Repeat this twice more with the rest of the stock so as to make a smooth sauce. Bring to a boil and allow to thicken and reduce for 1 - 2 minutes, then stir in the Italian herbs.

Tip: this technique is known as making a roux. For this, it's important that the quantities are precise; 1 tbsp butter is 15g and 1 tbsp flour is 20g.

Reheat the same frying pan over low heat and add the sauce, cream and a third of the cheese. Mix well to combine and cook gently for 2 - 3 minutes, seasoning to taste with salt and pepper. In the meantime, grease an oven dish with butter or olive oil. Cut the lasagne sheets according to the size of your oven dish.

Pour a layer of the filling into the oven dish and top with some of the lasagne sheets. Press down gently (see Tip). Top with another layer of the filling and then again with lasagne sheets. Repeat with the rest of the filling and lasagne sheets, being sure to reserve enough of the filling for the top of the lasagne.

Tip: this will ensure the sauce spreads evenly and the lasagne cooks more quickly.