Rinse the rice thoroughly and soak for 30 minutes.
Cut the mushrooms and beef into bite-sized pieces.
Season the beef with soy sauce, sugar, minced garlic, and sesame oil.
Add the soaked rice to the pot and spread it evenly.
Place the seasoned beef and prepared mushrooms on top of the rice.
Pour in water or broth and cover with a lid.
Cook for 10 minutes over medium heat, then another 10 minutes over low heat.
Let it rest for 10 minutes, mix well, and serve in a bowl.