1. The day before, soak the beans in cold water and let them soak overnight.
2. Prepare the dumpling dough: crack the whole eggs into a bowl and beat them. Crumble the chili pepper. Cut the butter into small cubes. Put the flour in a bowl and make a well in the center. Pour in the beaten eggs, egg yolks, chili pepper, and a pinch of salt, then knead.
3. Add the butter and knead everything until you obtain a homogeneous dough. Roll it into a ball and let it rest overnight in a cool place.
4. The next day, drain the beans. Cut the pig's tail into pieces. Peel and chop the scallions. Peel the garlic clove and cut it in half. Crumble the chili pepper.
5. Put these ingredients in a casserole dish and cover with a few centimeters of water. Let it cook for about an hour, until the beans start to soften.
6. Meanwhile, roll out the dumpling dough on a wooden board and cut out 10 cm diameter discs using a glass.
7. After the first cooking time for the beans, season them with salt and pepper. Place the dough discs on top and poach them for 10 minutes over low heat. Serve in the casserole dish.