Preheat the oven to 200C/180C Fan/Gas 6
Cook the macaroni in boiling water for 6 minutes. Add the broccoli and cook for another 2 minutes. Turn off the heat, add the spinach and leave to stand with the lid on for 2 minutes. Drain well and set aside
Heat the oil in a heavy-based frying pan. Fry the spring onions for 2 minutes. Add the garlic and fry for another 2 minutes. Add the flour and cook, stirring all the time, for 1-2 minutes. Slowly pour in the milk, add the bay leaves and season with salt and pepper. Continue simmering for 2-3 minutes, until thickened. Remove the bay leaves.
Stir in the mustard, lemon zest and three quarters of the Parmesan, then season well.
Tip the pasta and broccoli into a shallow baking dish. Pour over the sauce and mix well. Sprinkle over the remaining cheese and bake for 15-20 minutes.
Serve with the dressed salad leaves.