Preheat your oven to 425 f. and line a large baking sheet with parchment paper for easy cleanup afterwards.
Carefully cut your spaghetti squash in half lengthwise using a very sharp large chef’s knife, scoop out the seeds (I use an ice cream scoop to make this easier) and place it, cut side up, on your baking sheet.
Brush or spritz both insides lightly with half of your oil and season lightly with sea salt and pepper. Flip your squash cut side down onto your baking sheet and roast for 30-40 minutes.
Once the squash is finished roasting, remove from the oven. Turn them over by carefully flipping them back up like a boat and let cool slightly.
Use a fork to lightly scrape and loosen the 'spaghetti' strands from the inside of each squash.
Keep your oven preheated after removing the squash because we're going to place it back in at the end to melt the cheese.
Meanwhile, heat the remaining tablespoon of oil in a large skillet over medium heat. Add the chicken and cook until nicely golden and no longer pink.
Sprinkle with sea salt, pepper, garlic powder, onion powder and flour. Continue to cook until it begins to brown.
Add in your milk of choice milk and stir continuously until your sauce begins to thicken; this will take a couple of minutes.
Remove from heat and stir in the yogurt. Taste test and season with sea salt and pepper if desired.
Using a fork gently separate the spaghetti-like strands from the inside of your roasted squash.
Divide your chicken Alfredo sauce evenly and toss with the squash strands as shown. Sprinkle with mozzarella.
Return to the hot oven and bake for 10 minutes, or until the cheese is melted.
Garnish with fresh parsley, red pepper flakes, and/or freshly grated parmesan if you like.