Marinate the Chicken: In a bowl, combine olive oil, salt, pepper, Italian seasoning, and garlic powder. Coat the chicken thighs in the marinade. Let them sit for at least 30 minutes, or up to 2 hours for deeper flavor.
Preheat the Blackstone Griddle: Heat the Blackstone griddle to medium-high heat, about 375°F (190°C).
Cook the Chicken: Place the marinated chicken thighs on the preheated griddle. Cook for 6-7 minutes per side or until the internal temperature reaches 165°F (74°C) and they are golden brown.
Prepare the Cream Sauce: In a skillet over medium heat, add the minced garlic and sauté for 1 minute until fragrant. Pour in the heavy cream and bring to a simmer.
Add Cheese and Lemon: Stir in the Parmesan cheese and lemon juice. Allow the sauce to thicken slightly, stirring occasionally for about 3-4 minutes.
Combine and Serve: Once the chicken is cooked, place it in the skillet with the cream sauce. Spoon the sauce over the chicken and let it simmer together for an additional 2 minutes.
Garnish: Remove from heat, and sprinkle with chopped parsley before serving.
