Combine the tomatoes, red onion, olive oil, salt, and black pepper in a baking dish and mix well. Place the block of feta in the middle of the tomatoes and turn over once so the top is coated with olive oil. Cut the cream cheese into chunks and scatter over the tomatoes. Sprinkle red pepper flakes over the feta. Bake for about 35 minutes, or until the tomatoes start to burst.
Cook the pasta according to the package instructions. Drain, reserving 1 cup of the pasta cooking water.
Remove the feta mixture from the oven and stir in the chopped garlic, roasted red peppers, and ½ of the basil leaves, breaking up the cheese and tomatoes to make a creamy sauce. Add the cooked pasta and stir well to combine. Add the pasta water to thin the sauce, if needed.
