1. Preparation
Gather all ingredients: eggs, dashi stock, sugar, soy sauce, and salt.
In a mixing bowl, crack 4 large eggs.
Add 2 tablespoons of dashi stock to the eggs.
Add 1 tablespoon of sugar, 1 teaspoon of soy sauce, and a pinch of salt to the eggs.
Whisk the mixture thoroughly until well combined and slightly frothy.
Prepare a non-stick rectangular frying pan or a tamagoyaki pan, and brush it lightly with oil.
2. Cooking
Heat the pan over medium heat until hot but not smoking.
Pour a thin layer of the egg mixture (about 1/4 of the total) into the pan, tilting the pan to spread it evenly.
Cook the egg until the edges start to set but the surface is still slightly runny, about 1-2 minutes.
Using chopsticks or a spatula, carefully roll the cooked egg towards you, creating a tightly rolled cylinder.
Push the rolled egg to the back of the pan.
Add another thin layer of the egg mixture to the empty part of the pan, lifting the rolled egg so the new mixture can flow underneath.
Cook until set, then roll the existing roll forward, wrapping it with the new layer.
Repeat this process until all the egg mixture is used (about 4-6 layers).
Once finished, remove the rolled omelette from the pan and place it on a cutting board.
Let it cool slightly before slicing it into even pieces.
3. Serving
Arrange the sliced tamagoyaki on a plate.
Optionally, serve with a side of soy sauce or a sprinkle of thinly sliced green onions.