Begin by gathering all your ingredients. Dice the onion, carrot, and celery into small, uniform pieces to ensure even cooking. Cut the chicken breasts into bite-sized pieces for quicker cooking and easier serving.
In a large skillet, heat the olive oil over medium heat. Add the diced onion, carrot, and celery. Sauté for about 5-7 minutes, or until the vegetables are softened and the onion is translucent.
Add the diced chicken breasts to the skillet with the sautéed vegetables. Season with salt and pepper. Cook for approximately 6-8 minutes, stirring occasionally, until the chicken is browned and cooked through.
Pour in the can of crushed tomatoes with basil, oregano, and garlic. Stir well to combine all the ingredients. Bring the mixture to a simmer, allowing the flavors to meld together for about 10 minutes.
Stir in the grated Parmesan cheese and chopped fresh basil. Allow the cheese to melt and the dish to become creamy, about 2-3 minutes. Taste and adjust seasoning if necessary.
Remove the skillet from heat and serve the Tuscan Basil Chicken warm. It pairs wonderfully with crusty bread, over rice, or with a side of pasta for a complete meal.