Heat oil in a large deep skillet or pot over medium; cook garlic and pepper flakes 1-2 minutes until fragrant and just turning golden, watching carefully.
Add tomatoes, broth, oregano, salt, pepper, and optional sugar; stir and bring to a boil.
Stir penne into sauce, keeping mostly submerged.
Reduce heat to medium-low; simmer 12-15 minutes, stirring every few minutes to prevent sticking, until pasta is tender and most liquid absorbed.
Add a splash of water or broth if sauce thickens before pasta cooks; simmer uncovered a few extra minutes if too thin.
Off heat, stir in fresh basil; adjust salt and pepper flakes to taste.
Serve immediately with plenty of Parmesan and a drizzle of good olive oil if desired.