Put the rice in hot water for 30 minutes and then wash and drain. If you are using fresh leaves then put the leaves in boiling water for 5 minutes. Drain and remove the stems. If you are using preserved leaves then just remove the stems. You can put the stems at the bottom of the pan and this will prevent the bottom layer of stuffed leaves burning.
Place oil in a pan and saute the onions. Add the rice and stir for a few minutes. Add the tomatoes and the tomato puree. After 5 minutes add 1 cup of hot water and cook until the water evaporates. Add 1/2 cup of olive oil, dried mint, pepper, cinnamon, allspice, salt and sugar and mix.
Place a leaf on the counter and put 1/2 tsp of filling on the larger end of the leaf. Fold the two sides in and then roll it up like a cigarette. Don't roll them too tightly though. Place them side by side each other in a saucepan. Put the lemon slices n the top and add 2 cups of warm water. Put a small plate on top of the
vine leaves. Cover and cook on a low heat for 40 minutes, until the water has been absorbed.