In a large mixing bowl, combine the buckwheat flour and salt.
Gradually add water while mixing until a smooth, firm dough forms.
Knead the dough for about 5 minutes, then cover it with a damp cloth and let it rest for at least 30 minutes.
On a floured surface, roll out the dough into a thin sheet.
Cut the dough into thin strips to form noodles.
Bring a large pot of salted water to a boil.
Add the buckwheat noodles and cook for about 5-7 minutes, or until they are tender.
Drain the noodles and rinse them under cold water to stop the cooking process. Set aside.
In a large skillet or wok, heat the vegetable oil over medium heat.
Add the finely chopped onion and minced garlic. Sauté until the onion is soft and translucent.
Add the cooked buckwheat noodles to the skillet and toss to coat them with the onion and garlic mixture.
Stir in the soy sauce, sesame oil, and ground black pepper. Mix well to ensure the noodles are evenly coated.
Transfer the Puta to a serving dish.
Garnish with freshly chopped cilantro.
Enjoy your meal!