Chicken, Mushroom, Spinach Alfredo

I roasted a chicken last week and as always, had about half of it left over, so I thought about chicken alfredo and decided to boost it up with spinach and mushrooms (2 of our favorite ingredients). I lightened the jar of alfredo sauce that I had on hand with chicken broth.

2 Tbl butter
1 Tbl olive oil
1 large onion, diced
4 cloves garlic, minced
10 oz mushrooms, sliced
2 Tbl flour
1 1/2 cups chicken broth
1  15oz jar alfredo sauce (I used Classico 4 cheese)
3 - 4 cups diced cooked chicken
1/2 tsp black pepper
4 - 5 cups fresh baby spinach
Parmesan cheese for garnish

In a large saute pan, melt the butter and oil, and saute the onions, mushrooms and garlic until softened. Sprinkle the flour over the mixture and stir while still cooking for a couple of minutes.  Slowly add the chicken broth, alfredo sauce, and then the chicken and bring up to a boil.  Add the spinach leaves, a handful at a time and cook until the spinach wilts.  Add the pepper and serve over cooked pasta, garnished with parmesan cheese if desired