For the tzatziki, put the diced cucumber in a colander and sprinkle with salt, place the colander over a large bowl. Place a plate on top of cucumber, and then a heavy weight on the plate, refrigerate overnight to drain.
Place the muslin squares one on top of each other in a small strainer, and place the yoghurt in the centre. Bring the corners of the muslin together. Suspend the yoghurt in the strainer over a bowl and refrigerate overnight to drain.
Put the garlic and olive oil in a glass jar and stand to steep overnight, do not steep garlic for any longer than this.
For the lamb burgers, heat half olive oil in a large frying pan, add onion and cook over low heat to soften, but not coloured. Add garlic, cook for 30 seconds more, remove from heat and set aside to cool. (Reserve pan to cook burgers.)
Place torn pita bread in a large bowl, pour over ouzo and, using your fingers, massage ouzo into bread until a paste forms. To the same bowl, add mince, mint, rigani, cumin, cinnamon, salt, pepper and cooled onion mixture. Mix very well to incorporate all ingredients and shape into four patties.
Heat remaining oil in the reserved frying pan over medium high heat and cook patties for 4-5 minutes on each side or until golden and cooked through. Remove and set aside to keep warm. Add vine leaves to the pan in batches and cook on each side for one minute or until crisp.
Meanwhile preheat a large grill pan over medium high heat. Brush the eggplant slices with oil and cook for 3 minutes each side or until tender. Brush the pita quarters with oil and cook on grill for 1 minute each side or until crisp.
While they are cooking complete the tzatziki by combining the cucumber, drained yoghurt, garlic oil, lemon juice and salt and pepper to taste.
To serve, place one vine leaf on top of a pita quarter, top with patty, eggplant, a dollop of tzatziki, another vine leaf and finally another pita quarter. Serve with an extra shot of ouzo.
