Using a meat mallet, pound out the boneless skinless chicken breasts until they are uniform in size and about ½-3/4 of an inch thick.
In a large bowl, combine the chicken breasts, 1 tablespoon of Olive Oil, ½ teaspoon salt, ½ teaspoon of pepper, and 1 tablespoon of minced garlic. Stir to combine ingredients and coat chicken.
Place the chicken into a large saucepan and cook on medium heat for 3 minutes or until lightly browned. Once browned, flip the chicken over and cook the other side until lightly browned. Once all of the chicken is browned on both sides, remove it from the pan and place it on a plate or bowl until later. You aren't fully cooking the chicken in this step. Instead, you are just browning it.
Using the same pan, add 1 tablespoon of Olive Oil and 12 ounces of mushrooms. Cook on medium heat until the mushrooms are cooked and browned, stirring periodically.
Add 1 tablespoon of garlic, 1 teaspoon of thyme, and ¼ teaspoon of red pepper flakes (if desired). Stir for 1 minute.
Add in the heavy cream, lemon juice, lemon zest, and grated parmesan cheese. Stir for 3 minutes or until the cheese has incorporated into the sauce well.
Add the chicken breasts back into the pan with the sauce and cook for 5-10 minutes, or until the chicken has completely cooked through. Top with the shredded parmesan cheese.
Serve with your favorite side dishes. We love to serve Creamy Parmesan Garlic Chicken with pasta or mashed potatoes. Ladle the sauce right on top! Yummmmm!