drain and rinse grape leaves well until water runs clear.
remove the stems.
add 1/2 the oil to a large pot with a well fitting lid and spread around the bottom.
mix minced onion, remaining oil, meat, rice, molasses, allspice, 2 tsp garlic, salt, black pepper, and half of tomato paste in a large bowl.
Mix water, lemon juice, remaining tomato paste, and tablespoon of garlic in seperate bowl.
lay one layer of onion rings and tomato slices in pot.
lay one grape leaf vein side up with the top of the leaf pointing away from you, place about 2 tsp of filling at the bottom of the leaf (make it kind of like an oval). Turn the leaf up one turn away from you (rolling the leaf around the filling). Fold the sides in, and roll the leaf up to the top. Place the leaf seam side down in the pot.
Continue rolling remainging leaves and packing them tightly in the pot.
When you have made one layer, sprinkle the layer with some of the sauce.
Place a layer of onion rings and tomato slices, then another layer of grape leaves, with sauce on the top. Continue until all the leaves have been filled.
Make sure you have enough liquid to cover the leaves in the pot (you may need to add just a little more water).
Put a heavy heat proof plate on the top of the leaves, cover pot, and bring to simmer for 50-60 minutes.