For the meatballs: Mix all the meatball ingredients well. Knead for about 5-10 minutes. Set aside in the fridge for half an hour if you have time. Knead 1-2 minutes again when you take out. Shape them thick as a thumb and and long as your index finger.
For the sauce: In a saucepan add the olive oil and the butter. Heat up on the stove over medium heat; after butter is melted add the tomato paste, stir for a minute. Add the remaining sauce ingredients. Let simmer for 5 minutes and remove from heat.
Meanwhile grill the meat balls either on the stove or oven. If in the oven at 200° Celsius until brownish on all sides. If on the stove with olive oil and until again brownish on all sides. The meat balls should not be dry, make sure not to over cook.
For the pita bread: Cut the pita bread to small squares as in the picture. Use bread that is stale. Heat them up slightly on the stove in a skillet or in the oven.
Spread enough pita bread on each plate. The bread should be flat.
Pour the yogurt on the bread. If you like you can serve with just adding a few spoons on the side of the plate or completely leave out the yogurt.
Then place meatballs on bread for each plate. Pour the sauce on top and serve.