Step 1

In a medium bowl mix ricotta cheese, egg, Parmesan cheese, spinach. Stir well and set it aside.

Step 2

Lightly coat the inside of the slow cooker with cooking spray.

Step 3

Ladle about 1 cup of homemade tomato sauce on the bottom of the slow cooker and spread it well.

Step 4

Layer 5 or 6 zucchini slices to cover.

Step 5

Place some of the ricotta cheese mixture and top with the mozzarella cheese.

Step 6

Repeat the layers until all your ingredients are all used up.

Step 7

Top the lasagna with mozzarella and Parmesan cheese.

Step 8

Cover and cook on high for 3 to 4 hours.

Step 9

Turn off the slow cooker and let stand for about 1 hours. (UPDATE: Since some readers said the lasagna became a little soupy, I made it again and I let it stand for about 3 HOURS before serving. I found it was great because the liquid absorbed much more - Please, do not forget this step).

Step 10

Before serving top with fresh parsley