Preheat your oven to 350°F (175°C).

In a large skillet, heat 1-2 tablespoons of olive oil over medium heat. Add the sliced zucchini and season with a pinch of salt and pepper. Sauté for about 8-10 minutes, until tender and slightly golden brown.

Using the same skillet, add a bit more olive oil if needed and toss in the fresh spinach. Stir continuously for about 3-5 minutes, until wilted. Drain excess moisture.

In a mixing bowl, combine ricotta, Parmesan, egg, garlic, herbs, red pepper, and spinach. Mix until creamy.

Grease a 13 x 9-inch casserole dish with olive oil and pour a thin layer of marinara sauce.

Layer gluten-free lasagna noodles over the marinara, then add sautéed zucchini, half of the cheese mixture, and mozzarella.

Repeat the layering: another set of noodles, remaining zucchini, half cheese mixture, and more mozzarella. Finish with a final layer of noodles, remaining marinara, and mozzarella.

Cover with foil and bake for 30 minutes. Remove foil in the last 10 minutes to brown the top.

Let the lasagna cool for about 15 minutes before serving.