Preheat oven to 180°C. Fry 1 clove garlic and onion in a frypan until soft. Add mince and fry until browned. Add spices to taste and 1/2 of lemon rind. Cook 1 minute further. Remove from pan and place in a bowl.
Fry remaining garlic in the same pan and add the spinach. Cook for about 3 minutes, add remaining zest, stir and remove from heat.
In a large bowl, mix egg, ricotta, feta and spinach.
Lightly grease a pie dish. Layer the filo sheets over the dish, allowing the sheet to hang over the edge. Brush pastry lightly with milk between layers.
Place half the spinach mixture onto the pastry. Top with lamb mixture and top with remaining spinach.
Fold overhanging pastry over spinach and lamb mix. Lightly brush the top of the pie with milk.