Sprinkle both sides of the chicken with salt, pepper, and a little garlic powder. Heat olive oil and butter in a skillet over medium heat. Once hot, add the chicken, cooking each side for about 4–5 minutes until golden brown. Remove the chicken and set it aside.
Using the same skillet, lower the heat slightly. Add minced garlic and sauté for 30 seconds until fragrant. Pour in chicken broth, scraping the pan to loosen any browned bits. Add heavy cream and whisk in the ranch seasoning mix until the sauce is smooth and creamy.
Place the seared chicken back into the skillet. Spoon some sauce over each piece, cover the skillet, and reduce the heat to low. Allow the chicken to simmer in the sauce for 15–20 minutes until cooked through.
If you prefer a slightly crispy, baked texture, pour everything into a baking dish, sprinkle extra cheese on top, and broil for 5 minutes.