Take the ribeye steaks out of the refrigerator and let them sit at room temperature for about 30 minutes. Season both sides generously with salt and black pepper.

In a large skillet, heat 1 tablespoon of olive oil over medium-high heat. Once hot, add the steaks and sear for about 4-5 minutes on each side for medium-rare, or until desired doneness. Remove the steaks from the skillet and let them rest on a plate.

In the same skillet, reduce the heat to medium. Add 2 tablespoons of butter, minced garlic, rosemary, and thyme. Sauté for about 1-2 minutes until fragrant, being careful not to burn the garlic.

Add the chopped onion to the skillet and sauté until softened, about 3-4 minutes. Pour in the beef broth, soy sauce, and Worcestershire sauce, scraping up any browned bits from the bottom of the skillet. Bring the mixture to a gentle simmer.

Stir in the cornstarch slurry (cornstarch mixed with water) and cook for another 2-3 minutes, or until the gravy thickens. If the gravy becomes too thick, you can add a little more beef broth to reach your desired consistency.

Return the steaks to the skillet and spoon the gravy over them. Add the remaining 2 tablespoons of butter and let it melt into the sauce, enhancing the flavor.

Garnish with fresh parsley and serve hot with your choice of sides, such as mashed potatoes or steamed vegetables.