I always try and make recipes healthier when possible so I used skim milk and light ricotta. I also used a bigger pan, so I wasn't able to do as many layers. I put one thick layer of spinach mixture rather than two thin layers and two layers of squash rather than three.
Making the squash:
Making the spinach mixture:
Combine spinach, Ricotta cheese, mozzarella, garlic, salt and pepper.