First knead the flour, soy milk and 1 teaspoon salt with the dough hooks of the hand mixer, then with your hands to a smooth dough. Form into a ball, wrap in foil and chill for approx. 30 minutes
Wash the potatoes thoroughly and boil them in boiling water for about 20 minutes until soft. Drain potatoes, rinse briefly, peel while still hot and press through a potato ricer. Clean the leek, cut into thin strips and wash thoroughly. Chop the leek finely. Heat 1 tbsp. oil in a frying pan. Steam the leek in it for 3-4 minutes, season with salt. Peel garlic and chop finely. Drain the tofu, add to the potatoes with leek, lemon juice and garlic, mix and season with salt, pepper, nutmeg and sugar
Wrap the noodle dough from the foil, knead again with your hands and quarter it. Dust the dough balls one after the other with flour and cover. Roll out the dough balls with a pasta machine until they are thin, one after the other, up to level 5. Dust the dough with flour from time to time. Cut out circles with a round cookie cutter (approx. 8 cm Ø). Put 1 1/2-2 tsp. potato filling in the middle of each circle. Brush the edges with water, fold the circles into semicircles and press the edges together. Place the finished pasta on a floured baking tray
Bring plenty of salted water to the boil in a large pot. Simmer the noodles for 4-5 minutes, pour into a sieve. Wash and drain the sprouts. Wash chives, dab dry and cut into fine rings. Heat 6 tablespoons of oil in a coated pan. Fry the noodles for 2-3 minutes while turning. Add chives. Arrange noodles, sprinkle with sprouts