1Heat the olive oil in a large skillet over medium heat.
Add the chopped onion and garlic to the skillet and sauté until the onion is translucent, about 5 minutes.
Add the chicken breasts to the skillet and cook until browned on both sides, about 5-7 minutes per side.
Add the chopped tomatoes and chicken broth to the skillet. Bring to a simmer.
Reduce the heat to low, cover, and let simmer for 15-20 minutes, or until the chicken is cooked through.
Stir in the chopped basil and grated Parmesan cheese. Cook for an additional 2-3 minutes, until the cheese is melted and the basil is wilted.
Serve the Tomato Basil Chicken hot, garnished with additional basil and Parmesan if desired.