Begin by mincing the garlic and chopping the green chillies, cilantro, and tomatoes.

Heat oil in a shallow pot over medium heat, then add chopped garlic, green chillies, and tomatoes. Sauté for 2-3 minutes until fragrant.

Pour in enough water to cover sautéed ingredients and bring to a gentle boil over low heat.

Wash and peel the starchy potatoes. Boil in salted water until tender, about 15-20 minutes.

Using a wooden mortar, mash the boiled potatoes until almost doughy, ensuring no large lumps remain.

With wet hands, scoop out small portions of potato mixture and roll them into golf ball-sized balls.

Gently add potato balls to boiling broth and let cook for about 1 minute until they float.

Ladle soup into bowls, garnishing with cilantro and Sichuan pepper if desired. Serve hot.