Make the glazed carrots: Slice the carrot into rounds, and simmer slowly in a small pan. Reserve the cooking liquid.
Make the hamburgers: Chop the onion finely and sauté in butter until well browned. Grate the carrot in the meantime.
Put the onion, carrot, ground beef, eggs, and panko in a bowl and knead together. Add salt and pepper halfway through, and keep kneading. When the meat mixture comes together, form into patties.
Spread oil in a pan. When it's hot, add the hamburger patties and brown one side over high heat. When it has browned, turn over and brown the other side.
When both sides of the hamburgers are browned, add enough water to cover 1/4 of the thickness of the hamburgers. Cover with a lid and steam-cook.
When the hamburgers have a bouncy texture on both sides, turn the heat off and take them out.
Make the hamburger sauce: Wash the burnt bits out of the pan. Add the glazed carrot cooking liquid, tonkatsu (or Japanese Worcestershire-style) sauce and ketchup, and simmer until thickened.
Serve: Put the hamburgers on serving plates, add plenty of sauce, and put the glazed carrots on the side.
This is a variation using the hamburger mixture I made in advance. It's a yakiniku sauce flavored soboro rice bowl (Recipe ID: 1593571).
Story Behind this Recipe
My hamburger-loving husband came to this recipe after a lot of trial and error. The hamburgers are sweet, light and healthy.
Brown the hamburgers on both sides. Adjust the amount of breadcrumbs depending on the water content of the grated carrot. By adding some of the glaze from the carrots to the hamburger sauce, you'll be able to round out the flavors and make it even milder.