Prepare the Zucchini: Trim the zucchini and slice it thin lengthwise. Heat a skillet over medium heat, add olive oil, and sauté the zucchini slices for about 8-10 minutes until tender and golden.

Sauté the Spinach: In the same skillet, toss in the fresh spinach and cook for 2-3 minutes until wilted. Place it on a clean towel to drain excess moisture.

Preheat the Oven: Preheat your oven to 350°F (175°C) to ensure even baking.

Mix the Cheesy Filling: In a mixing bowl, combine ricotta cheese, rennet-free Parmesan, egg, minced garlic, wilted spinach, and fresh herbs. Season with salt, pepper, and crushed red pepper.

Assemble Your Lasagna: Coat a 13 x 9 casserole dish with cooking spray, spread ½ cup of marinara sauce, then layer gluten-free lasagna noodles, zucchini slices, cheesy spinach mixture, and mozzarella.

Create the Second Layer: Repeat with the remaining noodles, vegetables, cheesy mixture, and finish with marinara and mozzarella on top.

Bake the Lasagna: Bake in the preheated oven for about 30 minutes until cheese is bubbling and golden.

Cool and Serve: Allow to sit for 15 minutes before slicing to help the layers set.