Brown the beef: Heat the olive oil in a large frying pan over medium-high heat. Add the ground beef and break it apart with a wooden spoon. Cook until it turns a deep brown colour and you hear a steady sizzle—about 5 minutes. The fat should be rendered and the meat should look crumbly, not grey.

Sweat the aromatics: Toss in the diced onion and stir. Cook for 2–3 minutes until the onion turns translucent and smells sweet, not sharp. Add the garlic and cook for another 30 seconds until fragrant—your kitchen will smell like a trattoria.

Build the sauce: Pour in the chopped tomatoes and stir in the tomato purée, oregano, basil, salt, and pepper. Bring to a gentle bubble—you'll see small bursts breaking the surface. Reduce the heat to low and let it simmer for 10 minutes, stirring occasionally. The sauce will thicken slightly and turn a rich, brick-red hue.

Mix the ricotta layer: In a medium bowl, combine the ricotta, egg, and half the Parmesan. Stir until smooth and creamy—the mixture should be pale and thick, with no streaks of egg visible.

Assemble the lasagna: Spread a thin layer of the meat sauce (about a ladleful) across the bottom of a 20x30cm baking dish. This prevents the noodles from sticking. Place a layer of no-boil sheets on top, overlapping slightly if needed. Spread half the ricotta mixture over the noodles, then a third of the remaining meat sauce, and a handful of mozzarella. Repeat: noodles, ricotta, sauce, mozzarella. Finish with a final layer of noodles, the rest of the sauce, all remaining mozzarella, and the leftover Parmesan.

Bake with confidence: Cover the dish tightly with foil and bake at 190°C (170°C fan) for 20 minutes. Uncover and bake for another 10 minutes—the top should be golden brown and bubbling, with crispy edges and a cheese crust that crackles when you tap it with a spoon. Let it rest for 5 minutes before slicing so the layers hold together.