Peel the lotus root and slice it into thin rounds, about 0.3–0.5 cm thick. The uniform thickness ensures even cooking.
In a pot, add 2 cups of water and 1 tbsp vinegar. The vinegar helps remove bitterness and keeps the lotus root crisp. Bring to a boil and add the lotus root slices. Boil for 10 minutes to soften them slightly.
Drain and rinse under cold running water to stop the cooking process.
Return the lotus root to the pot and add water, cooking wine, soy sauce, sugar.
If you have dried kelp (dashima), add 1-2 small slices for umami. Remove it once the water starts boiling.
Bring to a strong boil, then reduce heat to medium and simmer.
After 10 minutes, once the lotus root turns a rich brown color, add corn syrup or rice syrup to give it a glossy finish.
Let it simmer for 30 minutes, occasionally stirring to ensure even coating.
Stop cooking when the sauce reduces and is almost at the same height as the lotus root. If the water evaporates too quickly, you can stop earlier.
Drizzle with sesame oil and sprinkle sesame seeds for added nuttiness.
Gently toss to coat, then plate and serve!