Rinse the lotus root under cold water. Using a vegetable peeler, remove the outer skin. Slice the lotus root into 3–4 mm (about 1/8–1/6 inch) rounds. If there are small brown spots in the holes, trim them out with the tip of a knife. Place the slices into a bowl of cold water with 1 tsp vinegar or a pinch of salt to prevent discoloration while you prepare other ingredients, and soak for 5–10 minutes. Drain and pat dry with paper towels.

Prep aromatics

Peel and finely mince the garlic. Thinly slice the green onions on a bias. If using carrot garnish, shred it now.

Sauce & Seasoning

Make the sauce

In a small bowl, whisk together soy sauce, rice vinegar, mirin (or sugar syrup), chili paste, water or stock, cornstarch, salt, and black pepper until the cornstarch is fully dissolved and mixture is smooth. Set aside.

Cook lotus root

Heat a large nonstick or stainless-steel skillet over medium-high heat. Add vegetable oil. When the oil shimmers, add the lotus root slices in a single layer (work in two batches if necessary to avoid overcrowding). Let the slices sear without moving for 2–3 minutes to get a golden surface, then flip and cook the other side for another 2 minutes. Stir and continue cooking for a total of 6–8 minutes until slices are tender-crisp and lightly caramelized. If lotus root sticks, reduce heat slightly and use a thin spatula to release.

Add aromatics

Push the cooked lotus root to the sides of the pan and add the minced garlic to the center. Sauté the garlic for 20–30 seconds until fragrant (do not burn). Mix the garlic into the lotus slices and add the sliced green onion (reserve a little for garnish).

Finish with sauce

Give the prepared sauce a quick stir (cornstarch may settle). Pour the sauce into the pan and stir to coat all lotus slices. Bring to a gentle simmer for 1–2 minutes; the sauce will thicken and glaze the lotus root. Add sesame oil, toss to combine, and cook another 30 seconds. Taste and adjust seasoning with a pinch more salt or a dash of soy if needed.

Serve

Transfer the glazed lotus root to a serving plate. Sprinkle with toasted sesame seeds, remaining green onion slices, and optional cilantro and shredded carrot for color and freshness. Serve warm as a side dish or as part of a larger meal.