Heat olive oil in a skillet over medium heat.

Add chopped garlic and sauté for one minute until fragrant.

Stir in diced tomatoes and fresh basil; continue cooking for an additional 2 minutes.

Add the cooked and cubed chicken to the skillet.

Sauté for about 5 minutes until the chicken is heated through.

Transfer the chicken mixture to a large serving bowl.

Toss the cooked penne pasta into the bowl with the chicken mixture.

Add shredded mozzarella cheese and gently toss until the cheese is evenly distributed.

Season the dish with salt and pepper according to taste.