Cut the chicken in half lengthwise to create four thinner pieces. Season both sides generously with salt, pepper, and garlic powder.
Add olive oil and butter to a skillet over medium-high heat. Heat the pan for a few minutes.
Cook the chicken for 5-6 minutes per side, or until nicely seared and cooked through. Transfer the chicken to a plate, then loosely tent with foil to keep warm. Turn off the heat during this transfer.
Return the heat to medium-high. Sprinkle flour and garlic into the skillet; ensure the pan is hot, warming it if necessary. Cook for about one minute, stirring often.
Pour in the chicken broth and whisk until the flour dissolves and the liquid reduces by half.
Stir in the cream and allow it to bubble gently for a few minutes until thickened to your desired consistency, reducing heat if boiling rapidly. Remove the skillet from heat and stir in the Parmesan until melted into the sauce.
Return the chicken and any accumulated juices to the skillet. Spoon some sauce over the chicken. Season with additional salt and pepper if needed, and sprinkle parsley over top.
