Bring a pot of water to a boil. Add 1½ tablespoons salt and cook 250 g penne pasta. Before draining, reserve some of the pasta water.
Heat 2 tablespoons extra virgin olive oil in a large skillet. Add 1 large onion, chopped, and ½ teaspoon salt, then stir and cook until the onion softens.
Add 4 garlic cloves, finely chopped, and stir them into the onion.
Pour in 400 g canned tomatoes. Break up the tomatoes with a wooden spoon and cook the sauce until it reduces and thickens.
Stir in the 6 fresh basil leaves, chopped, and ¼ teaspoon ground black pepper.
Pour in 120 ml heavy cream and stir until the tomato sauce is evenly creamy.
Add the drained penne and 3 large spoonfuls reserved pasta water. Toss until the creamy tomato sauce coats the pasta.
Add 60 g Parmesan cheese and stir until it melts into the sauce. Serve the creamy tomato penne pasta immediately.
Notes
Canned tomatoes: Break up the tomatoes thoroughly as they cook so the finished sauce coats the penne more evenly.Pasta water: I reserve it before draining the pasta because its starch helps loosen the sauce without making it watery.Parmesan: Finely grated cheese melts into the hot sauce more smoothly and is less likely to form clumps.Sauce consistency: Add the measured pasta water while tossing the penne so the tomato cream sauce spreads evenly through the pasta.