Fill a large pot with salted water and bring it to a boil. Add the rotini pasta and cook according to package instructions until al dente. Reserve about ½ cup of pasta water, then drain the pasta and set aside.
While the pasta cooks, heat 2 tablespoons of olive oil in a large skillet over medium-high heat. Add the diced chicken breast, seasoning it with salt and pepper. Cook until the chicken is golden brown and cooked through, about 6-8 minutes. Remove the chicken from the skillet and set aside.
In the same skillet, reduce heat to medium. Add the minced garlic and sauté until fragrant, about 1 minute. Pour in the crushed tomatoes and stir to combine, scraping up any browned bits from the chicken. Allow the mixture to simmer for 5 minutes to develop flavor.
Lower the heat and stir in the heavy cream. Slowly add the chopped fresh basil, saving a little for garnish. Let the sauce gently simmer for another 3-4 minutes until it thickens slightly.
Return the cooked chicken to the skillet and stir to coat it in the creamy tomato basil sauce. Add the drained rotini pasta, tossing everything together. If the sauce feels too thick, use a splash of reserved pasta water to loosen it up.
Turn off the heat and stir in the grated Parmesan cheese until melted and incorporated. Taste and adjust seasoning with salt and pepper as needed.
Plate the creamy tomato basil chicken rotini, garnish with the remaining fresh basil, and serve immediately. This dish pairs wonderfully with a simple green salad or garlic bread.
