Preheat oven to 400. Line a baking sheet with parchment paper. Cut a tiny piece of the bottom of each squash to ensure they are level and stand up without tipping over on the baking sheet. Spray each squash with olive oil and sprinkle with salt and cinnamon. Place them into the oven and bake for 35-40 minutes, or until the squash can be pierced easily with a fork.
Meanwhile, make the filling. Place the frozen chicken sausages on a plate and microwave for 30 seconds - 1 minute until they are thawed enough to cut. Cut each link into 1 inch pieces.
Heat 1 tbsp olive oil in a large skillet over medium heat. Add in the sausage pieces, onions, and minced garlic. Stir for 3-4 minutes until the onions become translucent and the garlic is fragrant. Stir in the raw spinach for 1-2 minutes until wilted. Beat the eggs together in a bowl. Push everything in the pan aside to form an opening in the middle. Pour the eggs in and stir them with a spatula until scrambled and cooked through. Toss the eggs with the sausage spinach mixture and season with salt and pepper to taste.
Mix the garlic aioli ingredients together in a bowl and store in the refrigerator until you're ready to serve.
When the squash is done, fill each half with some of the filling and top with a drizzle of the aioli. Enjoy!