Place a large (deep-ish) pan over medium heat (I used a 3-quart cast iron pan). Warm a little oil and add the onions. Sauté until translucent and fragrant, then add the garlic and cook for 1 minute.
Add the tomato paste, 2 tablespoon oil, and broth and mix well, then add the squash and season with salt and pepper. Mix again.
Cover and reduce heat to low-medium for about 15 minutes. Stir and replace cover, cooking another 10 minutes or until squash is tender. Top with a squeeze of lemon juice and the fresh parsley and serve.