Sometimes the standard portion of beef you will get in the US can be rather large, either at a restaurant or at a market. I bought a good sized NY strip steak the other day. It was almost 1 pound and I was told by the butcher that was considered one portion! I thought one portion would be enough for the two of us but we ended up using it in three additional dishes (aside from enjoying it as a steak on the first day). This was the third dish I made from the steak. I did not follow any recipe. This is a cross between beef donburi or gyu-don 牛丼 and roast beef donburi ローストビーフ丼. Instead of a raw egg, I topped it with a soft poached egg. I added fresh corn and spinach since I happened to have them available.
The yolk was almost totally runny but the egg white was cooked (Of course I used pasteurized eggs from Davidoson).
Again, I did not measure anything so this is not a recipe. I started with Japanese dashi broth (Bonito and kelp), added mirin, sugar and soy sauce to make a rather strong sweet and salty simmering liquid. I added thinly sliced onion and let it cook until the onion was translucent. I added fresh corn kernels (leftover from making shrimp balls) and spinach and cooked it until the spinach wilted (about 1 minute). At this point, the simmering sauce was a bit reduced too much so I added a small amount of hot water (from my InstaHot) and re-tasted it.
I sliced the NY strip streak thinly which was cooked medium rare. I placed on the top of the cooked vegetables and placed the lid and let it sit for 1 minutes to warm it up (not to cook). I placed the vegetables with the simmering liquid (it was just right amount of two servings) on the top of warm rice (I used microwaved previously frozen rice for this) as seen in above picture.
I covered the surface with warmed steak slices. Meanwhile I poached eggs (using pasteurized Davidson eggs) and top each donburi. We broke the yolk and let it mingle with sauce and meat. This dish was not roast beef don (which is usually served with Japanese style onion sauce) and flavor is more similar to gyu-don. This was our lunch on our off day and we thoroughly enjoyed it.