Dissolve dashi granules in warm water. Stir well. (makes 3 tablespoons of dashi broth so you can make a few tomagoyaki rolls)
In a bowl, add 1 tablespoon of the liquid dashi broth mixture, eggs, milk or dairy free alternative, sugar and mirin. Beat well until all ingredients are well incorporated.
Oil a makiyakinabe (rectangular egg rolling pan) or regular omelet pan well. We like to use an oil soaked paper towel to do this so there is not too much oil and make sure you get up on the sides of the pan too. Keep your oil near your pan as you will need to oil your pan between each new egg roll to prevent sticking.
Heat your pan to a medium heat. Test to see if your pan is ready by dripping a couple of drops of the egg mixture. If the egg mixture sizzles, you are good to go. Do not heat the pan so high that the pan is smoking. The heat should be a medium heat.
Pour ⅓ of your egg mixture into the pan. Tilt the pan so the egg covers the bottom of the pan. Use either chopsticks, a spatula or whatever you need to grab the edge of the egg omelet and roll carefully and gently vertically from one side of the pan to the end of the pan. Poke any bubbles that occur along the way. Make sure your egg roll end up at the end of the pan. If your pan gets too hot, turn down the heat on your burner or just lift the pan off the burner for a moment. You are going to add a total of 3 layers to your Japanese Egg Roll Tomagoyaki.
Oil your pan again and add ⅓ of the egg mixture to the pan. This time carefully lift the cooked egg roll in the pan and allow the liquid egg mixture to go underneath. Tilt your pan to each side and lift the edge of the cooked egg roll so that the uncooked egg gets around the sides of the cooked egg roll. Starting with cooked egg roll side, carefully grab and roll and keep your tomagoyaki down to the opposite side of the pan. Remember to poke holes with any bubbles that occur along the way. If the pan is getting too hot, take it off the heat for a moment and adjust your stovetop temperature.
Okay now for the last layer… Oil your pan again on the bottom and sides. Add the last ⅓ of egg mixture to the pan. Tilt up the cooked egg roll and allow the uncooked egg to get underneath the roll and on the side of the egg roll. Starting from the large cooked egg roll side, roll your tomagoyaki to the opposite side of the pan. Slowly and gently. Poke any bubbles that occur along the way. Allow your finished cooked Japanese egg roll tomagoyaki to sit at the edge of the pan for a moment. Do not worry if your egg is not completely cooked. The egg will continue to cook while resting in the wooden sushi roll.
Place your Japanese egg roll tomagoyaki in a wooden sushi roll and gently but firmly roll and hold to form a perfect circle. Allow your tomagoyaki to rest for about 3-4 minutes and if you want you can even place a plate on top for added pressure.
Place your tomagoyaki on a cutting board and with a sawing motion, slice your tomagoyaki roll into 8 slices. Serve and enjoy! いただきます (Itadakimasu) – Let’s Eat!