Over medium heat, drizzle a little oil into a saute pan. Add spinach and wait until it reduces in size and is soft, turning occasionally.
Add wilted spinach to a food processor and puree until smooth. (For frozen spinach, put defrosted spinach directly in food processor)
Cook and drain pasta according to package directions.
Melt butter in a pan over medium heat. Add flour, whisk and cook for one minute. Slowly add milk continuing to whisk until combined. Continue stirring and allow the rue to come to a slow bubble.
Add the shredded cheese and stir until cheese melts and is combined. Add nutmeg, cayenne, salt and pepper. Stir in spinach puree until combined. Add drained pasta to the cheese sauce and stir to coat pasta.
Serve immediately or pour into casserole dish, top with some additional shredded cheese if desired, and bake on 350 degrees just until the cheese is melty and bubbly. Enjoy!
I love that this recipe allows me to sneak in that extra serving of veggies!