Begin by heating a skillet over medium heat. Add thinly sliced zucchini and sauté for about 8–10 minutes until softened and slightly golden. Once cooked, set the zucchini aside. Next, add fresh spinach to the same skillet, sautéing until wilted, about 2–3 minutes. Drain any excess moisture.

In a large mixing bowl, combine ricotta cheese, grated Parmesan, and a beaten egg. Stir in minced garlic, fresh basil, parsley, and crushed red pepper. Gently fold in the cooked spinach, seasoning with salt and pepper to taste.

Grease a 13x9-inch casserole dish. Spread about ½ cup of marinara sauce on the bottom, then layer with gluten-free lasagna noodles, sautéed zucchini, half of the cheese mixture, and a sprinkle of mozzarella. Repeat the layers, finishing with noodles, marinara sauce, and mozzarella on top.

Preheat your oven to 350°F (175°C). Cover the lasagna with foil and bake for 30 minutes. Remove the foil and return it to the oven for another 10-15 minutes until the mozzarella is golden and bubbly. Let cool for 15 minutes before slicing.