Create the Sauce Base: In the same skillet (no need to clean it; the browned bits add flavor), melt the remaining 1 tablespoon butter. Add the 3 minced garlic cloves and cook until fragrant, stirring constantly for just about 30 seconds. Be careful not to burn the garlic.
Simmer & Thicken Sauce: Stir in the 1 cup low-sodium chicken stock, using a wooden spoon or spatula to scrape up any browned bits stuck to the bottom of the pan (this adds immense flavor). Reduce the heat to low. Stir in the 1 cup heavy cream, juice of 1 lemon, and the 1/3 cup freshly grated Parmesan cheese. Let the sauce simmer gently for 2-3 minutes, stirring occasionally, until it has thickened slightly and the flavors have melded. Season the sauce to taste with more Kosher salt, freshly ground black pepper, and additional lemon juice, if desired, for a brighter tang.
Finish Cooking Chicken & Serve: Nestle the browned chicken pieces back into the simmering sauce. Let them continue to simmer in the sauce for a few more minutes, or until the chicken is cooked through and reaches an internal temperature of 165°F (74°C). Garnish with fresh lemon slices or minced fresh parsley, if desired, before serving. Enjoy immediately with pasta, rice, or roasted vegetables to soak up that delicious sauce!
