In a blender or food processor, place the onion, scallions, garlic, salt, and pepper. Reserve.
Make a hole for the filling. With a long knife, make a hole in the center of the meat. Remove some of the meat from the center outwards, and reserve the meat for the filling.
With half the onion mixture, rub the main meat (not the stuffing), place it in a bag and let it cool for 4 to 5 hours.
Fill the meat with the carrot, the eggs, the meat you have taken from the center of the meat, and the rest of the onion.
As you fill, we push with your fingers to make sure the filling reaches the bottom.
Tie the end of the meat with fiber or thread so that the filling does not come out.
Wrap the meat with plastic wrap and foil, and place in a pot.
Cover with water and salt.
Cover and let cook over medium heat for about 3 hours.
If necessary, add more water.
After this time, remove from heat, remove the water and let stand.