Bring a large pot of salted water to a boil. Add the penne pasta and cook according to package instructions until al dente, usually about 10-12 minutes. Drain and set aside, reserving about ½ cup of pasta water to loosen the sauce later if needed.
In a large skillet, heat 1 tablespoon olive oil over medium-high heat. Add the peeled and deveined shrimp in a single layer and season lightly with salt and pepper. Sauté for 2-3 minutes on each side until the shrimp turn pink and opaque. Remove the shrimp from the skillet and set aside.
In the same skillet, reduce heat to medium and add the minced garlic. Sauté for about 30 seconds until fragrant but not browned. Add the drained diced tomatoes and stir to combine with the garlic. Let this cook for 2-3 minutes to warm through and allow the flavors to meld.
Pour in the heavy cream and stir well to combine with the tomatoes. Bring the mixture to a gentle simmer and let it cook for about 5 minutes, stirring occasionally, until the sauce thickens slightly.
Stir in the grated Parmesan cheese until melted and smooth. Then add the chopped fresh basil and optional red pepper flakes for a hint of spice. Taste and adjust seasoning with salt and pepper as needed.
Return the cooked shrimp to the skillet along with the drained penne pasta. Toss everything together gently to coat the pasta and shrimp evenly with the creamy tomato basil sauce. If the sauce seems too thick, add reserved pasta water a tablespoon at a time until you reach the desired consistency.
Serve immediately, garnished with extra basil or Parmesan if desired. This dish pairs beautifully with a fresh green salad or garlic bread for a satisfying meal.