Bring a large pot of salted water to a boil.

While the water heats, warm the olive oil in a large pan or pot over medium heat.

Add the chopped onion and cook until softened and translucent, about 5-7 minutes.

Add the sliced garlic (and red pepper flakes if using) and cook for another 1-2 minutes until fragrant, being careful not to burn the garlic.

Pour in the canned chopped tomatoes. Stir, season with salt and black pepper, and bring to a gentle simmer. Let it cook for 10-15 minutes, stirring occasionally, to allow the flavors to meld.

Add the pasta to the boiling water and cook according to package directions until al dente.

Before draining, scoop out about 1 cup of the pasta cooking water and set aside. Drain the pasta.

Add the drained pasta directly to the tomato sauce. Toss to coat, adding a splash of the reserved pasta water if needed to create a smooth sauce that clings to the pasta.

Stir in most of the grated parmesan cheese.

Serve immediately, topped with the remaining parmesan, fresh herbs (if using), and a drizzle of balsamic glaze (if using).