In a skillet over medium heat, cook onion and garlic in olive oil until soft. Add lamb and cook until browned. Drain the pan. Add remaining ingredients, except butter, fillo, egg, sesame seeds, and mint. Cook for at least 10 minutes. Mixture should be moist but not runny. If it’s dry, add a little stock. Set aside to cool.

Preheat oven to 350°F.

Lightly brush melted butter on one sheet of fillo pastry, edges first, then the center. Cover with another fillo sheet and butter it the same way. Repeat,
making three layers.

Spread lamb mixture thinly along the edge of the buttered pastry, leaving about 2 inches on each side. Fold the sides inward, then, starting from the edge with meat, roll the pastry into a tight cylinder shape.

Repeat, making three cylinders.

Form cylinders into one spiral shape (start from the center). To join cylinder ends, rub a wet finger along the seams (cylinders may not join smoothly). Brush entire spiral with egg wash. Sprinkle with sesame seeds and torn mint leaves. Bake for 25 minutes, or until pastry is golden.