Preheat the oven at 180°C (fan assisted) 200°C gas mark 5.
Wash the aubergines and cut lengthwise. Scoop out some of its flesh with the help of a spoon leaving an edge of 1/2 cm all around. Sprinkle some salt inside the aubergine and put it aside for few minutes. Repeat this with all aubergines.
Put the flesh as it is in a bowl and sprinkle salt on it. Put aside for a while.
Chop the onion and the leek finely and sweat it for 5 min with a sprinkle of salt.
In a bowl, put the ground beef on the egg, a pinch of salt (not too much as the aubergine flesh as well as aubergines and onions have some already) pepper, curry powder, finely grated carrot. Mix well.
Squeeze the aubergine flesh of any juices and chop finely. Add to the meat mix.
Turn the aubergine halves face down for 2 min so all juices inside.
Add the onion and the leek to the meat mixture and mix well.
Stuff the aubergines and pour some tomato juice over the top of it. Place in the preheated oven. You can sprinkle a generous amount of grated cheese over it.