Cut the chicken in half lengthwise so you have 4 thinner pieces. Season them on both sides with salt, pepper, and garlic powder.
Add the olive oil and butter to a skillet over medium-high heat, and let the pan heat up until butter is melted.
Add the chicken to the pan and cook for about 5-6 minutes per side or until it's nicely seared and cooked through to 165 degrees Fahrenheit. Transfer chicken to a plate and loosely tent it with foil to keep warm.
Turn the heat back on to medium-high and sprinkle in the flour, oregano, and garlic to the skillet. Let it cook for about a minute, stirring often.
Pour in the chicken broth and whisk until the flour has dissolved and the liquid has reduced by half.
Reduce heat to medium and stir in the heavy cream, letting it simmer for a few minutes until it thickens slightly, about 6-7 minutes.
Stir in the parmesan until it has melted into the sauce.
Add the chicken back to the skillet (and any juices from the plate) and spoon some sauce over the top. Cook for 2-3 minutes to warm the chicken back up.
Sprinkle the parsley over top and let rest for 2 minutes before serving.
