Roast the Vegetables: Preheat your oven to 200°C (180°C fan). On a large baking tray, toss the aubergine, courgette, and red pepper cubes with 1 tablespoon of olive oil, a good pinch of salt, and black pepper. Spread them in a single, even layer. Roast for 25-30 minutes, or until the edges are deeply caramelised, the aubergine looks shrunken and golden, and the kitchen smells sweet and smoky. Give them a stir halfway through for even colour.

Build the Tomato Sauce: While the vegetables roast, heat the remaining 1 tablespoon of olive oil in a large, deep frying pan over a medium heat. Add the chopped onion and cook for 6-8 minutes, stirring occasionally, until it becomes soft, translucent, and smells sweet. Add the minced garlic and cook for a further minute until fragrant. Pour in the tinned tomatoes and tomato purée, then add the dried oregano and basil. Stir well, bring to a gentle simmer, and cook for 15 minutes, or until the sauce has thickened and reduced slightly, turning a deeper, richer shade of red. Season with salt and pepper.

Prepare the Ricotta Mixture: In a medium bowl, combine the ricotta cheese, beaten egg, and half of the grated Parmesan. Mix until smooth and creamy. The mixture should be thick and spoonable, not runny. Season with a pinch of black pepper.

Layer the Lasagna: Spoon a thin layer of the tomato sauce (about 4-5 tablespoons) onto the bottom of a 23x33cm baking dish. This prevents the pasta from sticking. Lay down a single layer of lasagna sheets, breaking them to fit if necessary. Spread half of the ricotta mixture over the pasta in an even layer. Scatter half of the roasted vegetables on top, followed by a third of the torn mozzarella. Repeat this process: pasta, sauce, remaining ricotta, remaining roasted vegetables, another third of the mozzarella. Finish with a final layer of pasta, the last of the tomato sauce, and the remaining mozzarella. Sprinkle the top with the reserved Parmesan cheese.

Rest and Bake: At this point, you can cover the dish with foil and refrigerate for up to 24 hours. When ready to bake, preheat your oven to 180°C (160°C fan). Bake the lasagna, uncovered, for 40-45 minutes. You'll know it's ready when the sauce is bubbling enthusiastically around the edges, the cheese on top is melted and golden brown, and the whole dish is piping hot through to the centre. For an extra-luxurious, restaurant-style finish, switch the oven to a high grill for the final 2-3 minutes to create a deeply bronzed, blistering crust.

The Crucial Resting Period: This is the most important step for presentation. Remove the lasagna from the oven and let it rest on a wire rack for at least 15-20 minutes. This allows the layers to set and the liquids to be reabsorbed, meaning you will get clean, defined slices that won't collapse into a puddle on the plate. The dish will still be wonderfully hot.

Plate with Precision: Use a sharp, thin-bladed knife to cut the lasagna into neat squares. Using a large, flat spatula, carefully lift each portion onto a warmed plate. Wipe the edges of the plate with a clean, damp cloth for a pristine finish. Garnish each serving with a few fresh basil leaves and an extra grating of Parmesan.