01 - Bring a large pot of salted water to a rolling boil. Cook pasta according to package directions until al dente, then reserve 1/2 cup pasta water before draining.
02 - Heat olive oil in a large skillet over medium heat. Add chopped onion and cook 3-4 minutes until translucent and fragrant.
03 - Stir in minced garlic and cook for 1 minute until just fragrant, being careful not to burn.
04 - Add tomato paste and stir constantly for 1 minute to deepen flavor and remove raw taste.
05 - Pour in crushed tomatoes, sugar, oregano, and red pepper flakes. Season generously with salt and pepper. Simmer uncovered 8-10 minutes until slightly thickened, stirring occasionally.
06 - Reduce heat to low. Stir in heavy cream and grated Parmesan. Cook 2 minutes until cheese melts and sauce becomes velvety smooth.
07 - Add drained pasta to the skillet. Toss thoroughly, adding reserved pasta water as needed to achieve silky consistency. Serve immediately topped with fresh basil and additional Parmesan.