Directions

1. Heat a large non-stick frying pan until hot. Add about half the mince and fry it over a medium heat for 4-5 minutes until browned. Stir it with a wooden spoon and press out any lumps while it is frying. Tip the browned mince into a bowl. Tip the remaining raw mince into the pan and add the garlic and oregano. Fry it as you did with the previous batch, then return all the mince to the pan and mix it together.
2. Tip in the mushrooms and roasted veg sauce, and squirt in the ketchup (you can be generous). Season with black pepper and salt if you like. Stir well to mix everything together, turn the heat up under the pan and bring to the boil, then turn it down so it bubbles gently. Cover the pan and cook for 30-35 minutes, stirring every 10 minutes to mix everything together. As it cooks, the mushrooms will shrink and make the mince more saucy.
3. While you're waiting for the meat to cook, break the egg into a large bowl and beat it with a whisk or fork to break up the white and the yolk. Pour the cream into the bowl, then grate about two thirds of the cheese and add to the bowl. Be careful, a grater looks innocent enough, but it's sharp so mind your fingers. Season with a good grinding of black pepper. Beat well to mix. Now turn the oven on to 180C/gas 4/fan 160C.
4. Lay the lasagne in a dish and cover with boiling water. Leave for 5 minutes. Take an ovenproof dish measuring about 28-30cm x 22-23cm and 7.5cm deep. Spread about a couple of spoonfuls of meat sauce over the bottom, then cover with 3-4 sheets of lasagne (lift them out of the water with tongs) overlapping them slightly to make them fit if you need to. Drizzle over just a little of the cheese sauce - about 2-3 spoonfuls.
5. Spoon over half the remaining meat and spread it out, right to the edges of the dish. Cover with 3-4 more sheets of lasagne, then spoon over the remaining meat, spreading it out evenly and almost to the edges. Cover with 3-4 more sheets of lasagne.
6. Pour what's left of the cheese sauce over the top. Jiggle the dish so the sauce runs to the edges and squelch the corners of the pasta into the sauce so there's none poking up. Grate the rest of the cheese evenly all over, then grate over about 1/2 teaspoon of nutmeg. Bake in the oven for 30 minutes or until bubbling and golden. Leave to stand for 5 minutes before decorating the top if you like. Cut into 6 portions and serve with a salad.