Cook pasta according to package instructions. About 5 minutes before pasta is done, add just half of the chopped broccoli to the pot. Once done, drain the pasta and broccoli and transfer to a casserole dish. Set aside.

Make sauce by melting butter over medium heat. Add flour and whisk until it creates a paste. Whisk in small amounts of milk at a time until all of the milk has been incorporated.

Bring the sauce to a boil. Stirring frequently, mix in the chopped spinach, peas, remaining broccoli, and some salt and pepper. Simmer, uncovered, on low for 5-10 minutes. While simmering, preheat oven to 400°F (200°C).

Turn off heat and stir cheese and nutmeg into the sauce. Season with salt and pepper to taste.

Optional: Transfer all or part of the sauce to a blender and blend until smooth.

Pour sauce over pasta. Bake 20-25 minutes until golden. Serve.