Step 1: Bring a large pot of salted water to a rolling boil. Add pasta and cook according to package directions until al dente. Reserve about 1.5 cups of the starchy pasta water before draining the pasta.
Step 2: While the pasta cooks, heat 3 tablespoons of extra virgin olive oil in a large skillet or pan over medium heat. Add the sliced garlic and red pepper flakes (if using). Sauté for 1-2 minutes until the garlic is fragrant and lightly golden. Be careful not to burn it.
Step 3: Add the cherry tomatoes to the skillet. Increase the heat to medium-high. Cook for 5-7 minutes, stirring occasionally, until the tomatoes start to burst and blister. Using the back of a spoon or a potato masher, gently ‘smash’ about two-thirds of the tomatoes to release their juices and create a rustic sauce. Keep some whole for texture.
Step 4: Pour in 1 cup of the reserved pasta water, the balsamic vinegar (if using), and bring the sauce to a simmer. Season with salt and black pepper to taste. Let it cook for another 3-5 minutes, allowing the sauce to thicken slightly and the flavors to meld.
Step 5: Add the drained al dente pasta directly into the skillet with the tomato sauce. Toss vigorously to combine, ensuring every strand of pasta is coated. If the sauce looks too thick, add a splash more of the reserved pasta water until it reaches your desired consistency.
Step 6: Remove the skillet from the heat. Stir in the fresh basil leaves. Drizzle with the remaining 1 tablespoon of extra virgin olive oil. Taste and adjust seasonings one last time.
Step 7: Serve immediately, garnished with freshly grated Parmesan cheese and an extra grind of black pepper if desired.