01 - Pat the chicken breasts dry and season both sides evenly with salt, freshly ground black pepper, dried oregano, and dried basil.
02 - Heat the olive oil in a large skillet over medium-high heat. Add the seasoned chicken breasts and cook for 5 to 6 minutes per side until golden brown and cooked through to an internal temperature of 165°F. Remove from the skillet and set aside on a plate.
03 - In the same skillet, add the finely chopped onion and sauté for about 3 minutes until softened. Stir in the minced garlic and cook for 1 additional minute until fragrant.
04 - Add the halved cherry tomatoes to the skillet and sauté for 3 to 4 minutes until they begin to soften and release their juices. Pour in the chicken broth and bring the mixture to a gentle simmer.
05 - Stir in the chopped spinach and cook for approximately 2 minutes, tossing gently, until just wilted.
06 - Return the seared chicken breasts to the skillet, nestling them into the tomato-spinach mixture. Simmer for another 2 to 3 minutes until the chicken is heated through and the flavors meld together.
07 - Transfer to serving plates and sprinkle with grated Parmesan cheese if desired. Serve immediately alongside rice, pasta, or cauliflower rice.