Green Macaroni and Cheese

1. Preheat the oven to 350 F.
2. In a large pot of salted boiling water, cook the macaroni until just shy of al dente (should be about 6 minutes but refer to your package instructions and cook for just shy of al dente according to them). Before draining pasta, remove ½ cup of boiling water for the spinach. Set that aside, then drain and rinse pasta with cold water. Set aside.
3. In a small pan over medium-low heat, melt the 2 tablespoons of butter and then add the onions and jalapeno. Let them gently cook over medium-low heat for 7-10 minutes. Remove from heat and set aside.
4. In the jar of a blender, add the 6 cups of spinach and the 1/2 cup of hot water from the pasta. You probably will need to use a spoon to push the spinach down. Blend to a fine, bright green puree. Set this aside.
5. In the pot that you used to cook the pasta, melt the 1/2 cup of butter over low heat. Then add the flour into the melted butter. Stir until smooth and cook over low heat about 1 minute.
6. Add the milk and stir until very smooth. Simmer about 1-2 minutes until slightly thickened.
7. Add the cheeses and stir and stir until melted, very smooth and thickened.
8. Add the spinach puree and stir until smooth. Season to taste with kosher salt.
9. Pour the pasta into the pot of sauce, and add the onions and jalapeno and toss until everything is well combined.
10. Pour the macaroni into a 9x13x2” baking dish. Bake for 30 minutes until golden around the edges. Serve hot!