Arrange your hamburger patties in a deep frying pan, then cook on both sides until cooked. (It's okay if it doesn't cook all the way through here).
Once cooked, add the sauce and simmer. Add the vegetables and mushrooms at this time to simmer together to make it even more delicious This time, I added onions.
Flip the burgers over occasionally and cook the burgers through. Once the sauce thickens, it's done.
You can also use it in a bento the next day!
Story Behind this Recipe
The recipes I saw on Cookpad for simmered hamburgers didn't have sugar, so they were all a bit too sour for me... I wanted to have something a little sweeter for kids, so I tried it this way. These basic hamburgers are delicious and great for locomoco rice bowls.
It's hard to cook potatoes or carrots all the way through this way, so first heat in the microwave, then simmer. Simmering the hamburgers will ensure they're not under-cooked, but they will be soft and juicy.