Heat the 5 cups of broth in a medium sauce pan over medium heat. Bring it to a simmer and then turn it to low.
In a heavy-bottomed pan or Dutch oven, heat the olive oil and butter until the butter melts. Add the garlic and remaining corn kernels. Sauté until the garlic is very fragrant.
Add the Arborio rice and stir so that every grain gets coated in the olive oil and butter. Allow the rice to toast a bit, stirring occasionally. Once it starts to smell nutty, add the pureed corn. Stir occasionally until almost all of the puree has been absorbed by the rice.
Turn the heat off under the broth, and add a couple of ladles to the rice. Stir occasionally until, again, almost all of the liquid is absorbed. Repeat this process until the risotto is creamy and the rice is no longer al dente.
Add the Parmesan cheese, stirring until it has been incorporated. Add salt and pepper, to taste.
Top the risotto with roasted cherry tomatoes and fresh basil.