In a medium bowl, combine the ground beef with garlic powder, onion powder, sea salt, and black pepper.
Form the beef mixture into two equal-sized oval patties, about 3/4-inch thick.
Heat the olive oil in a large skillet over medium-high heat.
Place the patties in the skillet and sear for 4-5 minutes per side until deeply browned and cooked through. Remove the patties and set them aside on a plate.
In the same skillet, add the sliced mushrooms and diced onions. Sauté for 5-6 minutes until the vegetables are tender and the onions are translucent.
In a small jar or bowl, whisk the arrowroot powder into the beef broth until no lumps remain.
Pour the broth mixture and coconut aminos into the skillet with the vegetables. Stir constantly as the sauce simmers and begins to thicken.
Reduce the heat to low and stir in the full-fat coconut milk to create a creamy texture.
Return the beef patties to the skillet, spooning the mushroom gravy over them to coat thoroughly before serving.