Creamy fennel and leek lasagna

Heat a drizzle of olive oil in a frying pan over medium-high heat. Fry the fennel, leek and onion for 6 - 8 minutes. Add the garlic and fry for 1 more minute. Remove the pan from the heat and set aside.

Meanwhile, melt a knob of butter in a large 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 and fresh oregano.

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.

Add the fried vegetables, cream, and a third of the cheese to the saucepan. 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 vegetable sauce into the oven dish and top with some of the lasagne sheets. Press down gently (see Tip). Top with another layer of the sauce and then again with lasagne sheets. Repeat with the rest of the sauce and lasagne sheets, being sure to reserve enough of the sauce for the top of the lasagne.

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