Prep the oven and squash: Preheat oven to 400°F (200°C). Carefully halve the spaghetti squash lengthwise and scoop out the seeds. Drizzle cut sides with a little oil and sprinkle with salt and pepper. Place cut-side down on a parchment-lined baking sheet.

Roast the squash: Bake for 35–45 minutes, until the strands pull away easily with a fork and the squash is tender but not mushy. Let cool slightly, then use a fork to scrape out the strands into a large bowl. Pat dry with paper towels to remove excess moisture.

Cook the bacon: While the squash roasts, cook bacon in a skillet over medium heat until crispy. Transfer to a paper towel-lined plate and crumble when cool.

Make the creamy sauce: In a mixing bowl, beat together cream cheese, Greek yogurt, chicken broth, ranch seasoning, garlic powder, onion powder, smoked paprika, black pepper, and salt until smooth. If the cream cheese is too firm, microwave it for 15–20 seconds to soften.

Combine the filling: Add the shredded chicken, most of the bacon (reserve a bit for topping), cheddar, mozzarella, green onions, and peas (if using) to the bowl. Fold in the spaghetti squash strands. Mix until everything is evenly coated in the sauce.

Taste and adjust: Try a small bite and adjust salt, pepper, or ranch seasoning to your liking. Remember the flavors will soften a bit after baking, so season assertively but not overly salty.

Assemble the casserole: Lightly coat a 9x13-inch baking dish with cooking spray. Spread the mixture evenly in the dish. Sprinkle with a little extra cheddar or mozzarella if you want a cheesier top, and scatter the remaining bacon over it.

Bake: Reduce oven to 375°F (190°C). Bake uncovered for 20–25 minutes, until the casserole is hot, bubbly around the edges, and the top is lightly golden.

Finish and garnish: Let it rest for 5–10 minutes to set. Top with fresh green onions and, if you like, a light drizzle of ranch.

Serve: Scoop into bowls or squares. Pair with a crisp salad or roasted veggies for a balanced meal.