Rinse the tomatoes and remove any stems. Leave them whole, or halve larger cherry tomatoes.

Warm the olive oil in a large skillet over medium heat. Add the garlic and optional red-pepper flakes, cooking for 30–60 seconds until fragrant without browning the garlic.

Add the tomatoes, kosher salt, and optional black pepper. Stir to coat the tomatoes in the seasoned oil.

Cook uncovered for 12–18 minutes, stirring occasionally, until the tomatoes soften, split, and release their juices.

Gently crush some tomatoes with the back of a spoon or a potato masher, leaving some pieces intact for a rustic texture. Simmer for another 2–5 minutes, adding water if the sauce becomes too thick.

Stir in the basil, taste, and adjust the salt and pepper. Toss the sauce with hot pasta and finish with Parmesan or Pecorino if desired.