Melt butter in a medium-sized saucepan. Add in the chopped onion, garlic, and mushrooms and cook until the onion is translucent, 2-4 minutes.
Whisk in the flour and cook for 30 seconds. Add in the half and half, stirring so that no flour clumps remain. Bring to a soft boil, then reduce the heat and let simmer for 5-8 minutes, stirring occasionally.
Add in the Italian seasoning, cheese, and salt and pepper to taste.
Add in the artichoke, spinach, and cooked chicken, stirring to combine. Serve over cooked pasta!
Recipe by at https://www.ideahacks.com/chicken-pasta/