Cook pasta according to package instructions. Drain and rinse with cool water to cool. Transfer to a large bowl. Make sure the bowl allows enough room to stir the ingredients together without spilling.
Mix pesto and mayo together and gently stir in with the pasta. Gently fold the tomatoes, basil, and cheese into the pasta. I like to reserve a small amount of tomatoes, cheese, and basil for topping, but this is optional and it can all be mixed in the to salad.