Begin by heating the olive oil in a large skillet over medium-high heat. Season the chicken breasts with salt and pepper on both sides. Once the oil is hot, add the chicken to the skillet. Sear the chicken for about 6-7 minutes on each side, or until it's golden brown and cooked through. Remove the chicken from the skillet and set it aside.
In the same skillet, reduce the heat to medium and add the minced garlic. Sauté for about 1 minute, or until fragrant, being careful not to burn it.
Next, pour in the chicken broth and lemon juice, stirring to combine. Allow the mixture to simmer for a few minutes, scraping up any brown bits from the bottom of the skillet for added flavor.
Pour in the heavy cream, and then add the garlic powder and Italian seasoning. Stir well to combine. Allow the sauce to simmer for another 5 minutes, letting it thicken slightly.
Stir in the grated Parmesan cheese until it’s melted and incorporated into the sauce. This will give the sauce its creamy and cheesy consistency.
In a small bowl, mix the cornstarch and water until smooth. Slowly add this mixture to the sauce, stirring continuously until the sauce thickens to your desired consistency.
Return the seared chicken breasts to the skillet, coating them in the creamy lemon Parmesan sauce. Cook for an additional 2-3 minutes to heat the chicken through and allow it to absorb some of the sauce.
Plate the chicken and spoon the sauce generously over the top. This dish pairs beautifully with pasta, rice, or a fresh green salad.