Heat 2 tablespoons olive oil in a large saucepan or deep skillet over medium-high heat.
Season the chicken breasts with 1/4 teaspoon salt, 1/8 teaspoon pepper, and 1/4 teaspoon dried basil on both sides.
Sear the chicken in the hot oil about 5 minutes per side, until the internal temperature reaches 165°F (no pink remains). Remove the chicken to a plate and set aside.
Add the minced garlic to the pan and cook about 30 seconds until fragrant.
Pour in 2 cups chicken broth. In a separate bowl, whisk 1 cup evaporated milk with 2 tablespoons cornstarch until smooth, then add it to the pan and stir to combine.
Season the liquid with 1 teaspoon salt and 1/4 teaspoon ground black pepper, then bring to a simmer.
Add 3 cups dried elbow macaroni to the simmering liquid and cook, stirring occasionally, about 10 minutes until the pasta is tender and sauce has thickened.
Stir in 2 cups grated Parmesan and 1 cup grated mozzarella until melted and the sauce is smooth.
Fold in 1/2 cup halved cherry tomatoes and 1/4 cup fresh basil.
Slice the cooked chicken and return it to the pan, mixing gently to combine and warm the chicken through.
Drizzle with balsamic glaze if desired and serve warm.