In a large pot of boiling salted water, cook lasagna noodles according to package instructions.
Heat olive oil in a large cast iron skillet over medium high heat. Add garlic, onion, zucchinis and carrot. Cook, stirring occasionally, until tender, about 3-4 minutes.
Stir in ground turkey and cook until turkey has browned, about 3-5 minutes, making sure to crumble the turkey as it cooks; season with salt and pepper, to taste. Drain excess fat.
Stir in tomatoes, tomato paste and Italian seasoning until well combined; bring to a simmer until thickened, about 8-10 minutes. Stir in spinach until wilted, about 1-2 minutes.
In a medium bowl, combine ricotta, Parmesan and egg; set aside.
Preheat oven to 350 degrees F. Lightly oil a 9x13 baking dish or coat with nonstick spray.
Spread 1 cup tomato mixture onto the bottom of a 9×13 baking dish; top with 3 lasagna noodles, 1/2 of the ricotta cheese mixture and 1 cup mozzarella cheese. Repeat with a second layer. Top with remaining noodles, tomato mixture and remaining 1/2 cup mozzarella cheese.*
Place into oven and bake for 35-45 minutes, or until bubbling. Then broil for 2-3 minutes, or until top is browned in spots.
Let cool 15 minutes. Serve, garnished with parsley, if desired.
Notes
*MAKE-AHEAD: Cover lasagna tightly with plastic wrap. Refrigerate up to 24 hours. To bake, remove plastic wrap, cover and bake for 40 minutes. Uncover; bake for an additional 10-15 minutes, or until completely cooked through.*TO FREEZE: Cover lasagna tightly with plastic wrap, then aluminum foil. Freeze up to 3 months. To bake, remove plastic wrap, cover and bake for 90 minutes. Uncover; bake for an additional 10-15 minutes, or until completely cooked through.*TO FREEZE AFTER BAKING: Let the lasagna cool completely; cover tightly with plastic wrap, then aluminum foil. Label, date and freeze up to 3 months. To reheat, thaw overnight in the fridge and reheat in the oven at 350°F, covered in aluminum foil until warmed through, about 1 hour.