Preheat your oven to 375°F (190°C) and grease a 9x13 inch baking dish.

In a large skillet, heat a tablespoon of olive oil and sauté finely chopped onion and minced garlic for 3-4 minutes.

Add ground beef and cook for 6-8 minutes until browned. Season with salt and pepper, and add marinara sauce. Let it simmer for 10 minutes.

Combine ricotta cheese, one egg, and grated Parmesan cheese in a medium bowl. Mix until smooth, seasoning with salt and pepper.

Grill or roast zucchini slices for 2 minutes on each side to remove excess moisture.

Layer zucchini strips, half of the meat sauce, half of the ricotta mixture, and mozzarella in your baking dish. Repeat the layers and finish with mozzarella on top.

Bake for 25 minutes until golden brown and bubbly.

Let the lasagna rest for 10 minutes before serving, garnishing with fresh basil leaves.