Preheat oven to 180°C/350°F Place Eggplant, courgette, mushrooms and capsicum in a roasting pan, coat with 4 tablespoons of oil, season with salt and pepper, and bake for 25 – 30 minutes.
Heat the remaining 1 tablespoon oil in a large pan, add onion and garlic and saute until onion is translucent. Add crushed tomatoes and herbs and simmer for 10 minutes. Remove from heat and stir through roasted vegetables.
In a large bowl mash ricotta with a fork and mix in egg and basil. Blanch spinach in a pot of boiling water for 30 secs or until wilted. Drain and add to ricotta mixture. Leave aside.
For the cheese sauce melt butter in a saucepan over a medium heat, add flour and stir until mixture becomes frothy. Slowly pour in milk, whisking as you go. Bring to a boil, and whisk as mixture thickens. Remove from heat, stir in cheese and season with salt and pepper.
In a large greased baking dish spoon half the roast vegetable sauce, followed by a layer of lasagna noodles, trimming noodles to fit dish if needed. Spread the ricotta mix on top, followed by another layer of noodles. Spoon over remaining half of sauce, followed by a layer of noodles. Pour over cheese sauce, sprinkle with extra grated cheese and bake for 30 – 40 minutes, or until golden brown.