Beef Lasagna with Creamy White Sauce

Heat the oil in a large deep pan over medium heat. Cook the onion and carrot with a pinch of the salt for 6 to 7 minutes, stirring often, until soft and lightly golden. Stir in the garlic for 30 seconds.

Add the beef mince and turn the heat up to medium-high. Break it into small pieces with a wooden spoon and cook for 8 to 10 minutes, until no pink remains and any liquid has evaporated.

Stir in the tomato paste and cook for 1 minute. Add the chopped tomatoes, water, oregano, basil, pepper and remaining salt. Bring to a gentle bubble.

Lower the heat and simmer, partly covered, for 30 minutes, stirring now and then. The sauce is ready when it is thick and spoonable, not watery. Taste and adjust the salt.

While the sauce simmers, make the white sauce. Melt the butter in a medium saucepan over medium-low heat, add the flour and whisk for 1 to 2 minutes without letting it brown.

Pour in the milk a little at a time, whisking constantly to avoid lumps. Keep stirring over medium heat for 6 to 8 minutes until it coats the back of a spoon like thin custard. Season with nutmeg and a little salt, then remove from the heat.

Heat the oven to 180°C (160°C fan). Spread a thin layer of the white sauce over the base of the baking dish, then cover with a layer of lasagna sheets, breaking them to fit.

Spoon over one third of the beef sauce, then one third of the remaining white sauce, and scatter with a quarter of the mozzarella. Repeat the layers twice more, starting each time with pasta.

Finish with a last layer of pasta, the rest of the white sauce (make sure every sheet is covered so it cooks through), then the remaining mozzarella and the parmesan.

Cover tightly with foil and bake for 30 minutes. Remove the foil and bake for 15 minutes more, until the top is golden and bubbling at the edges and a knife slides easily through the pasta.

Rest the lasagna for 10 minutes before cutting so the layers set and slice cleanly.