Preheat oven to 400°F and line a baking sheet with parchment paper.
Halve the tomatoes and peel the garlic cloves, then toss with half the olive oil and a pinch of salt on the baking sheet.
Place the chicken breast on the same sheet, drizzling with the remaining olive oil and seasoning with the remaining salt and pepper.
Roast for 20-25 minutes until tomatoes are blistered and chicken is cooked through to an internal temperature of 165°F.
Remove the chicken from the oven and slice into bite-sized pieces, then set aside.
Transfer the roasted tomatoes and garlic to a high-speed blender along with the tomato puree, vegetable broth, and fresh basil.
Blend on high until the mixture is completely smooth and velvety.
Pour the soup into a medium pot and warm over medium heat for 5 minutes to marry the flavors.
Divide the soup into bowls and top each with the sliced roasted chicken and freshly grated parmesan cheese.