Step 1: Preheat your oven to 400°F (200°C).
Step 2: In a large roasting pan or on a baking sheet, combine the tomatoes and peeled garlic cloves.
Step 3: Drizzle generously with olive oil, then season with salt, black pepper, and red pepper flakes (if using). Toss gently to ensure all tomatoes and garlic are lightly coated.
Step 4: Roast for 30-40 minutes, or until the tomatoes are soft, slightly shriveled, and caramelized around the edges, and the garlic is golden and fragrant.
Step 5: While the tomatoes are roasting, bring a large pot of heavily salted water to a rolling boil. Add the pasta and cook according to package directions until al dente. Reserve about 1 cup of the pasta cooking water before draining.
Step 6: Carefully transfer the roasted tomatoes and garlic into a large skillet or directly into the pot with the drained pasta.
Step 7: Add the cooked pasta to the skillet with the roasted tomatoes. Add about 1/2 cup of the reserved pasta water and toss vigorously, using tongs, to create a silky sauce that clings to the pasta. Add more pasta water a tablespoon at a time if needed, until desired consistency is reached.
Step 8: Remove from heat. Stir in the torn fresh basil leaves and the 1/4 cup of grated Parmesan cheese.
Step 9: Taste and adjust seasoning as needed. Serve immediately, garnished with extra fresh Parmesan cheese and a drizzle of good quality olive oil or balsamic glaze, if desired.