• Preheat your oven to 400°F (200°C) degrees.

Prepare the spaghetti squash

• Cut the spaghetti squash in half lengthwise and scoop out the seeds.
• Brush the cut sides with olive oil and season with salt and pepper and place the halves cut-side down on a baking sheet.
• Roast in the preheated oven for about 40-50 minutes or until the flesh can be easily scraped with a fork to create "spaghetti" strands. Let it cool slightly before handling.
• Remove the spaghetti squash from the oven and using a fork remove the spaghetti. Set aside to cool.

Make the turkey filling

• In a large skillet, heat the olive oil over a medium heat.
• Add the chopped onion and cook until translucent.
• Add the minced garlic and sauté for another minute.
• Add the ground turkey and cook until browned and cooked through.
• Pour in the marinara sauce, seasoning and stir well. Let the mixture simmer for about 10-15 minutes.

Prepare the cheese layer

• In a bowl, mix together the ricotta cheese, spinach, 1 cup of the mozzarella cheese and parmesan. Season with salt and pepper.
• Stir in the spaghetti squash flesh.

Assemble

• Place the spaghetti squash shells on a baking tray or in a baking dish.
• Spoon a layer of the turkey mixture in the base of the spaghetti squash shell.
• Add a layer of the cheese mixture and repeat the layers.
• Top with the remaining mozzarella cheese and bake for 20 minutes until the top is golden.
• Serve and enjoy.