01 - Preheat the oven to 400°F.
02 - In a large baking dish, add cherry tomatoes, garlic, red onion (if using), olive oil, oregano, red pepper flakes, salt, and pepper. Toss to coat evenly.
03 - Make a space in the center and place the block of feta cheese. Drizzle a bit more olive oil over the feta.
04 - Roast for 30–35 minutes, until the tomatoes burst and the feta is golden and soft.
05 - Meanwhile, cook the pasta in a large pot of salted boiling water according to package instructions until al dente. Reserve ½ cup pasta water, then drain.
06 - Remove the baking dish from the oven. Using a fork or spoon, mash and mix the feta and tomatoes together to create a creamy sauce.
07 - Add the drained pasta and most of the basil to the dish. Toss everything together, adding reserved pasta water as needed to achieve your desired sauce consistency.
08 - Serve immediately, garnishing with extra basil and freshly ground black pepper.