Heat olive oil in a large skillet over medium heat. Add chopped onion and cook until softened and translucent, about 5 minutes. Stir in minced garlic and cook for another minute until fragrant, careful not to burn.
Pour in canned diced tomatoes with juices and chicken or vegetable broth. Stir in dried basil, salt, and pepper. Bring to a gentle boil.
Add dry penne pasta directly to the simmering tomato mixture. Stir to submerge pasta. Cover skillet and simmer, stirring occasionally, until pasta is al dente and has absorbed most of the liquid, about 12-15 minutes.
Reduce heat to low. Stir in heavy cream and grated Parmesan cheese until sauce is creamy and smooth. Adjust seasoning with salt and pepper if needed.
Remove from heat and sprinkle fresh basil leaves on top. Serve immediately, optionally with garlic herb focaccia or a crisp green salad.