Rinse the cooked white rice briefly in a colander under water.

Crack the egg into a bowl and beat it lightly.

In a small pot, combine the canned scallops (including the liquid), sake, and water. Heat over medium heat until boiling, then skim off any foam.

Add the seasonings (mirin and salt) and the rinsed rice to the pot. Once the mixture starts to simmer, pour in the beaten egg and turn off the heat.