Bring a large pot of water to a boil. Add 1 tablespoon of salt and the pasta. Cook according to package instructions until al dente (usually 8-10 minutes).

Reserve 1/2 cup of pasta water before draining the pasta. Drain pasta and set aside.

While the pasta is cooking, heat olive oil in a large skillet or saucepan over medium heat.

Add the diced onion and sauté for 3-4 minutes until softened and translucent.

Add the minced garlic and red pepper flakes (if using). Cook for 30 seconds until fragrant, being careful not to burn the garlic.

Pour in the crushed tomatoes. Add dried oregano, dried basil, sugar, salt, and black pepper. Stir to combine.

Bring the sauce to a simmer and cook for 10-12 minutes, stirring occasionally, until it starts to thicken slightly.

Reduce heat to low and slowly stir in the heavy cream. Allow the sauce to gently simmer for 2-3 minutes until slightly thickened. Do not boil.

Add the grated parmesan cheese to the sauce and stir until melted and incorporated.

Add the drained pasta to the sauce and toss to coat thoroughly. If the sauce is too thick, add some of the reserved pasta water, a little at a time, until you reach your desired consistency.

Cook for an additional 1-2 minutes, allowing the pasta to absorb some of the sauce.

Remove from heat and stir in most of the fresh basil, reserving some for garnish.

Serve immediately in warm bowls, topped with additional grated parmesan cheese and remaining basil and parsley if desired.