Preheat oven to 425 degrees.

Slice eggplant in half lengthwise. Cut each half lengthwise into 3 slices. Cut off rounded sides of the 2 outer slices so they lay flat.

Cut zucchini & squash into 1/2-inch wide slices.

Set out a few layers of paper towels (to use to transfer cooked veggies to drain excess moisture)

Spray a large pan with nonstick spray and bring to medium-high heat on stove.

Lay zucchini & squash flat in pan and cook for 3 minutes per side. Remove from pan and place on paper towels.

Re-spray pan & cook eggplant slices for 3 minutes per side. Remove from pan and place on paper towels.

In a small dish, combine spinach, ricotta, basil, minced onion, salt, & garlic powder. Stir well, set aside.

Spray a deep oven-safe pan with nonstick spray. Place half of the marinara in the center of the pan, and place 2 eggplant slices side by side over the sauce.

Spread about 1/4 of the spinach mixture on top of each slice. Then layer about 1/4 of the zucchini and squash slices on top of each stack. Over the veggie layer, add another eggplant slice.

Spread the rest of the spinach mixture on top of the stacks. Layer remaining zucchini and squash slices.

Cover stacks with remaining eggplant slices. Finish it off with the rest of the marinara, and a sprinkle of Parmesan cheese.

Bake in oven for 20-25 minutes. Remove from oven, sprinkle mozzarella cheese on top of each stack, and return to oven for 5 more minutes, or until cheese melts. Enjoy!