Preheat your oven to 200°C (400°F). Halve the tomatoes and lay them cut-side up in a baking dish with the garlic. Drizzle olive oil, and season with salt and pepper. Roast for 20 minutes, then cover with foil and roast for another 10 minutes.

While roasting, bring a large pot of salted water to a boil. Add the pasta and cook according to package instructions until al dente. Reserve 1 cup of pasta water, then drain the pasta.

In a blender, combine roasted garlic, blistered tomatoes, fresh basil, ricotta cheese, and chili flakes. Add ¼ cup reserved pasta water and blend until smooth.

In a large skillet set over medium heat, combine the sauce with the drained pasta. Toss well and adjust the sauce's consistency with reserved pasta water as needed.

Serve with fresh basil and a sprinkle of Parmesan cheese. Drizzle with olive oil if desired.