Preheat oven to 200°C/fan 180°C/gas 6 and line a baking tray with baking paper.
Brush pumpkin and aubergine with olive oil, season with salt and pepper and place in a single layer on prepared baking tray. Bake for 15-20 minutes, or until tender. Cool slightly.
Meanwhile, in a bowl whisk together passata and garlic and season with salt and pepper to taste.
In a small bowl, mix together ricotta, egg, parmesan and milk until well combined. Season with salt and pepper, to taste.
To assemble lasagne, place half of the passata mixture in the bottom of an oven proof dish and add half the basil leaves. Layer over half the pumpkin and half the aubergine and spread with half the ricotta mixture. Repeat layering. Finish with a layer of passata, followed by the remaining basil and cover with mozzarella. Season with pepper and bake for 30-40 minutes until cooked through and golden.
