Mince the onions and add to a heat-resistant plate. Cover with wrap and microwave for 2 minutes. Set aside and leave to cool.
Add the ground meat -> the onions from Step 1 -> the egg -> the rice -> and the panko to the bowl and mix together. Mix in the ☆ ingredients. Continue to mix until it's sticky.
Form the mixture into a hamburger shape. Pound the meat to remove any air, and make a shallow well in the center.
Cook in an oiled frying pan on low to medium heat for 2 minutes. Turn over, cover with a lid, and cook on low heat for 5 to 6 minutes. Once it's cooked remove the hamburger steak.
In the frying pan from Step 4, add the steak sauce ingredients, except for the margarine. Bring to a boil. Add the margarine last and bring to a simmer again.
Cover the hamburger with the steak sauce and it's done.
Story Behind this Recipe
I thought up this hamburger with an elegant steak sauce that's neither Japanese-style or demi-glacé.
Be careful not to burn the sauce when simmering it. It'll make the flavor bitter. These hamburger steaks don't use caramelized onions, so they're a bit healthier than your usual kind. Mixing in rice grains will make them even plumper.