Preheat the oven to 200°C.
Boil the macaroni for 6 minutes.
Add broccoli for another 2 minutes, then add spinach and stand for 2 minutes before draining.
Fry the spring onions and garlic in oil for 4 minutes total.
Stir in flour for 2 minutes, then slowly whisk in milk and bay leaves.
Simmer for 3 minutes until thickened and remove bay leaves.
Stir in mustard, lemon zest, and 75g of cheese.
Combine pasta, vegetables, and sauce in a dish.
Top with remaining cheese and bake for 15-20 minutes.
Serve with lemon-dressed salad leaves.