This pasta dish features sweet caramelized onions mixed into a creamy sauce of garlic, heavy cream, and Parmesan. The onions are cooked low and slow until golden, then combined with the sauce for a savory-sweet flavor. Cooked pasta is tossed in the sauce with a little pasta water for smoothness. The final dish is garnished with fresh parsley and extra Parmesan. It's a perfect balance of richness and sweetness.