Heat the oven: Preheat to 400°F (200°C). Grab a medium baking dish that fits the tomatoes snugly.
Build the base: Add tomatoes, olive oil, sliced garlic, red pepper flakes, salt, and pepper.
Toss to coat. Nestle the whole Boursin right in the center.
Roast: Bake 20–25 minutes, until tomatoes burst and Boursin is melty and soft around the edges.
Cook the pasta: While it roasts, boil pasta in well-salted water. Reserve 1 cup of starchy pasta water before draining.
Make the sauce: Mash the roasted tomatoes and Boursin together in the baking dish until creamy. Add a splash of pasta water to loosen.
Combine: Add drained pasta to the sauce.
Toss, adding more pasta water as needed until glossy and well coated.
Finish: Taste and adjust salt and pepper. Fold in chopped basil or parsley. Add lemon zest or a squeeze of lemon if you like brightness.
Serve: Top with Parmesan and extra herbs.
Eat immediately while it’s silky and hot.