½teaspoongarlic salt or ¼ teaspoon garlic powder + ¼ teaspoon salt
Cooking spray
9 uncooked lasagna noodles
Instructions
Squeeze the water from the thawed frozen spinach. I thaw mine in the microwave (remove wrapping from the box first-some have metal in them). Microwave on high for about 1 minute and break it up in chunks with your hands, then microwave it again for about 30 seconds.You can press the water out in a colander with the back of a spoon but I have better luck by squeezing it with my clean hands.
Combine the spinach in a large bowl with the chicken, cream of chicken soup, milk, sour cream, 2 cups of the mozzarella cheese, ½ of the Parmesan cheese, onion (if using), and garlic salt. Be sure to hold out the remaining cheese to put on top.
Coat the slow cooker pot with cooking spray. Arrange 3 of the lasagna noodles in the bottom of the slow cooker pot, breaking them in half as necessary to fit. It's ok that not every inch is covered.
Spoon one third of the spinach mixture over the top of the first layer of lasagna noodles. Then, repeat the layers of lasagna noodles and spinach mixture ending with the last one-third of spinach mixture on the top.Sprinkle the remaining 1 cup of mozzarella cheese and Parmesan cheese over the top.
Place the lid on the slow cooker and cook on LOW for 4 ½ to 5 hours or until the edges are browned and the mixture is bubbly.
Notes
Note: I don't recommend trying to shorten the cooking time by cooking it on HIGH. It needs the low and slow temperature for the noodles to soak up the moisture in the spinach mixture.Note: An oblong/oval slow cooker is better than a tall round one because it creates more surface area. A 6 to 7 quart slow cooker will be too large.Substitutions: In place of the 2 cans of cream of chicken soup and 1 ½ cups milk, use two 15-ounce jars Alfredo sauce.