Planet Hollywood Spinach Dip

1 1/2 cups heavy cream
1/2 cup yellow onions
1 1/4 cups sliced mushrooms
1/4 cup butter
2 tablespoons all-purpose flour
1/2 cup shredded mozzarella
1 teaspoon salt
1 teaspoon pepper
1/2 teaspoon Italian seasoning
1/2 cup sour cream
1 pound spinach

Cook onions and mushrooms in saucepan, and slowly add in remaining ingredients, adding the spinach last. Once all the ingredients are mixed in together, top with cheese. Serve with nacho chips. Can also serve with tomato relish.