I began by cooking my onions in a LARGE (preferably with a high rim, 4 quarts or larger in size) saute pan with a bit of nonstick cooking spray, after about 3-4 minutes, I added in the garlic. I cooked that down for a couple minutes– I then added in the sour cream and the fat free cream cheese. Once the cream cheese is melted, I added 1/4 cup of Parmesan cheese (save the other 1/4 cup for the end)
When the Parmesan cheese is fully melted I added in the artichoke hearts and spinach. Cook until the spinach is wilted. Add in the cubed chicken breast to the mixture. Give a good stir to fully incorporate.
Lastly, add in your cooked spaghetti squash, remaining 1/4 cup of Parmesan, 1/2 cup mozzarella, salt, pepper, and the chopped fresh parsley. Mix well. I used kitchen tongs to help mix– it will be a large portion.