Preheat oven to 375°F (190°C). Grease a 9x13 inch baking dish with olive oil.

Toss butternut squash cubes in olive oil, salt, and pepper; roast at 400°F (200°C) until tender (about 20 minutes).

In a skillet over medium heat, sauté spinach in a splash of olive oil until wilted (3-5 minutes).

Mix ricotta with beaten egg, Parmesan, basil, and oregano in a bowl until combined.

Assemble the lasagna: layer marinara sauce at the bottom, followed by noodles, half of the roasted squash, half of the sautéed spinach, ricotta mixture, and mozzarella. Repeat layers finishing with noodles topped with marinara and remaining mozzarella.

Bake uncovered for about 45 minutes until bubbly and golden brown. Let cool before slicing.