Mix the meat, burghul, onion, pastes and seasonings in a large bowl. If ingredients are dry, use water to bind them all up. Place cling wrap over bowl and refrigerate.
To make filling, first fry off the onions in a third of the butter until a golden yellowish colour. Then, add the meat and another third of the butter. Brown well. If you have chosen to add pine nuts, toss them through the meat and onion mixture.
Take out the meat mixture from fridge and spoon into tablespoon-sized balls (will make about 15 large meatballs). Make sure the mixture is firm.
Take one meatball and press the tip of your thumb into it to make a hole, and firmly hold the ball while you spin it around your thumb while making the hole bigger so you can fit 1 tablespoon of the filling. Then close the opening of the ball and shape into an oval shape. Put the meatballs in the back of the fridge to hold their shape and set.
To make yogurt soup, bring all wet ingredients to a large cooking pot and boil on high, till the mixture is thickened, stirring occasionaly. After it's boiling, add rice and all other ingredients for the yogurt soup. Turn heat to medium and stir this occasionaly so the rice doesn't stick to bottom of cooking pot. When the rice is half cooked, add the meatballs one by one and let it cook for another 20-30 minutes on a medium gas or electric stove top. Add extra salt, to taste.
Serve with hot crusty Turkish bread and a sprig of fresh parsley on top.