Preheat the oven to 200°C degrees and grease a 36cm by 25cm baking dish with olive oil.
Blanch the broccoli and asparagus in a pan of boiling salted water for 3 minutes. Soak the lasagne sheets in a large bowl of container of cold water, preferably in a single layer to prevent them from sticking (you may need to do this in batches).
For the green sauce, heat a frying pan to a medium heat and add 2 tablespoons of olive oil. Add the onion and fry for 7-8 minutes to soften, followed by the garlic for another min. Then add the spinach and fry for 2 minutes until it starts to wilt. Add the hot stock and simmer everything for 2 minutes before adding to a blender with the lemon juice, dried chilli and season generously with salt and pepper. Blend to a smooth consistency + set aside.
For the bean béchamel, melt the butter in the same saucepan that you used for the green sauce. Then, add the garlic and cook for 1 min before adding in the beans, nutmeg, cheese and water. Bring to a simmer for 1 minute and use a wooden spoon to break up most of the beans into the sauce - you want to leave a few of the beans whole for texture. Check for seasoning and remove from the heat.
Spoon a few ladles of the green sauce onto the bottom of the greased baking dish and make a single layer of lasagne sheets. Then, add another layer of green sauce, followed by a few spoonfuls of bean béchamel. Scatter over one third of the broccoli, asparagus, few basil leaves torn in, torn pieces of mozzarella, black pepper and gratings of parmesan.
Repeat this process until you have 3 layers of pasta.
The top should be green sauce, white sauce and any remaining cheese. Dot over a few more knobs of butter. Bake at 200C for 35 mins or until golden on top.
Serve with a fresh side salad and eat straight away.
