Add the beef, egg, almond flour, Parmesan, onion, garlic powder, salt, and pepper to a mixing bowl and combine well.
Form beef mixture into 4 oval patties.
Heat the butter and avocado oil in a large cast iron skillet over medium heat until hot.
Add the beef patties and cook for 5 minutes, covered.
Remove the lid, flip the patties and cook for 4 more minutes or until cooked through.
Remove the patties from the pan and set aside. Drain grease from the pan.
To make the gravy:
Add the butter to the skillet over medium heat and let melt. Stir in the garlic powder and xanthan gum and cook for 30 seconds.
Stir in the beef broth and Worcestershire sauce and bring to a simmer over medium heat, stirring often. Cook until mixture has thickened, about 5 minutes.
Taste and season gravy with salt and pepper.
Add steaks back to the skillet with the gravy and cook for 2 minutes to warm, topping the steaks with the gravy.