Mix together the ground beef, garlic powder, onion powder, salt, and pepper in a large mixing bowl. Divide the mixture into fourths and form into patties.
Over medium heat, heat a cast iron skillet or large skillet. Add the patties to the heated skillet and sear patty on both sides. Continue to cook burger to your desired temperature, up to 15 minutes total.
While the patties are cooking, make the Hawaiian Moco Loco gravy. Whisk together the beef broth, cornstarch, bouillon, garlic powder, onion powder, and Worcestershire sauce in a small saucepan.
Place the saucepan over medium heat and cook, stirring occasionally so it doesn't stick or burn. Make sure the bouillon cube breaks up, and cook until the mixture thickens, which typically takes about 8 minutes. Take it off the heat and stir in the butter and heavy cream, and set aside.
Heat a separate nonstick skillet over medium heat. Add the butter to the pan and let it melt. Crack the eggs into the pan and season with salt and pepper to taste. Cook until eggs are sunny side up or over easy, per your preference.
To serve, add hot rice to your serving plate. Top with burger patty, add gravy then an egg on top. Garnish with green onions, serve and enjoy.