Bring a large pot of salted water to a boil. Cook tortellini according to package instructions. When finished cooking, drain the tortellini in a colander.
Meanwhile, cook the chicken. In a large skillet, heat the olive oil over medium high heat. Add the chicken to the pan and season to taste with salt and pepper. Cook, stirring occasionally, until chicken is browned and just cooked through, 4-5 minutes.
Pour the tortellini in a large bowl. Add cooked chicken pieces and tomatoes. Gently stir in the basil pesto, stirring until the tortellini, chicken, and tomatoes are well coated with the pesto. Add the freshly chopped basil and season with salt and black pepper, to taste. Garnish with fresh basil and parmesan cheese, if desired.