Wash the rice and rinse until the water becomes clear. Put the rice in a heavy-bottomed pot or in rice cooker (if using) and soak with 4 cups of water for about 1 hour. When 1 hour is over, DO NOT DISCARD THE SOAKING WATER. Use the water to cook the rice in a heavy-bottomed pot or rice cooker. If using heavy-bottomed pot, bring the water to a boil and then lower the heat to let it simmer until the water almost all evaporated. Cover with lid and cook over low heat for the next 30 minutes or until the rice is cooked through and fluffy
In another pot, mix the sake, mirin, and the dashi stock and bring to a boil. Add in the sugar and let it cook for about 5 minutes. Add in the onion and let it simmers for another 5 minutes. Add in the soy sauce and beef and cook for another 5 minutes. Pour the beaten eggs over the beef and cover the pot. Let the eggs cook for about 2 minutes. The eggs should be cooked through by then
Portion the rice you prepared earlier into a bowl. Ladle the beef and eggs mixture over the rice and also some of the sweet broth and get ready to chow and be impressed
Notes
Refer to making Dashi stock at http://whattocooktoday.com/ichiban-dashi-stock-the-first-brew.html