onion and sauté until softened, about 5 minutes. Add the beef and garlic, raise the heat to medium-high, and cook, breaking the meat apart with a wooden spoon, until the meat is browned, 3 to 5 minutes. Add the tomato puree and tomato paste and season with salt and pepper. Reduce the heat to low and simmer while you prepare the squash. Peel the squash and slice it into very thin, uniform rounds; remove the seeds and fiber. Add
