1. On a smooth surface, sift the flour making a volcano. In the center, place the melt butter, the egg yolk and a pinch of salt.
2. Start by adding water little by little. Now knead the mixture until you geat a soft and homogeneous dough. If needed, add more wather to the mixture. The dough has to be soft, not dry.
3. Once you have the dough, make some ball shapes with the hands and with a rollin pin stretch them until you get a rectangle larger than the sausage, so you can wrap it.
4. Then, place the sausage in the middle of the rectangle, and sprinkle some grated cheddar cheese. Now wrap the dough around the sausage, sealing the corners like a letter.
5. Pre-heat the oven at 356ºF for 15 minutes.
6. Cover the oven dish with foil and spread butter on the surface. Now place the wrapped sausages and brush them on top with beaten egg.
7. Cook them at 356ºF until they´re brown, between 10 or 15 minutes. Serve them.