1) In a large sauté pan over medium-high heat, add the oil. Once heated, add: minced beef, onions, rice and garlic and sauté until the mince has browned. Remove from heat; stir in parsley, dill, salt, pepper and oregano. Set aside to cool a bit.
2) Place grape leaves in a bowl and pour water over leaves. Soak for 15 minutes and drain. Transfer leaves, dull-side down, to kitchen paper to dry.
3) Preheat oven to 190C/Gas Mark 5.
4) Stuff grape leaves using 1 heaping tablespoon mixture in centre of the dull-side of the leaf and fold outer parts toward the centre; and roll up like you would a burrito. Do not roll too tightly.
5) Arrange rolls in side by side layers in a deep baking pan. Once complete, fill the pan with water to the top of the grape leaves and place the butter on top. Cover with foil and bake 1 hour or until the water has been absorbed by the grape leaves.
For the lemon sauce:
1) In large pot bring chicken to the boil, reduce heat and add cornflour slurry so it has a consistency of gravy. Have egg whites you have whipped up in a large bowl and add gravy to them slowly folding in. Be careful not to cook the whites, only temper them. Whip until you have a creamy consistency and add in lemon juice.
2) You may have to add more lemon juice to get the right lemon flavour.
3) Plate up the grape leaves, and pour sauce on top.