Preheat your oven to 400°F (200°C). Cut the spaghetti squash in half, scoop out seeds, drizzle cut sides with olive oil, then sprinkle with salt and pepper. Roast cut side down on a foil-lined baking sheet for 35 to 45 minutes until tender.

While the squash roasts, heat a large skillet over medium heat and add a tablespoon of olive oil. Add the seasoned chicken breasts and sauté for 6-8 minutes per side until cooked through. Remove chicken and let rest before slicing.

In the same skillet, add more olive oil if needed and sauté the baby spinach for 2-3 minutes until wilted. Return sliced chicken to the skillet.

Lower the heat and add cream cheese, shredded Parmesan, and milk. Stir continuously for 3-4 minutes until creamy sauce forms, adjusting seasoning if necessary.

Scrape out the roasted spaghetti squash strands and add to the skillet with chicken and spinach. Stir in Greek yogurt until well coated. Top with mozzarella cheese and cover to cook on low until cheese melts (2-3 minutes).

Serve in plates or a bowl, sprinkle with parsley, and enjoy warm.