We live about an hour from the place where they serve the original version of this dish, but on our days off we want to enjoy our meals in leisure, so we stay in and make this at home instead. I've been making this for breakfast quite often recently.
Make the sauce. Put the sauce ingredients in a small pan, and simmer until reduced by half. What's shown in the photo here is 3 times the amount that the recipe here yields.
Put some rice in a bowl and pour on the sauce.
Heat 1 tablespoon of oil (not listed in the ingredients) in a frying pan and lightly fry the roast pork slices. Put the slices on top of the rice.
Make a fried egg with a soft-set yolk. Season generously with salt and pepper.
Put the fried egg on top of the roast pork, and pour on some more of the sauce. Sprinkle on some chopped green onion to taste.
Try this all-purpose sauce for pork rice bowls (Recipe ID: 1062992). It goes perfectly with this dish.
If you make this with home-made roast pork, it'll taste really authentic.
Story Behind this Recipe
Roast pork and egg rice is a B-class gourmet speciality of Imabari in Ehime prefecture. I tried making this with a sauce recipe I rely on all the time, and it was delicious. I don't think it's any different from store-bought sauce.
The authentic version apparently uses the reduced marinade from the roast pork.
Recently, I've started to think that ham can be used for this too. In our case, there's a bigger chance of having some ham around the house rather than roast pork. Hope you give this a try too!