As a child, I would eat this often in my father's hometown. I recall asking for a second helping of rice.
It was a local cuisine in the fishing village, where you could sun-dry freshly harvested wakame. I tried it out with more commonly available dried wakame.

Do not cook on high heat or else it will be bitter when burnt.
As soon as it's aromatic, remove from heat.
Do not soak the wakame in water. This is important.
The resulting flavor is slightly sweet. Adjust the amount of sugar to your liking. Recipe by Poron526