Preheat the oven to 200°C (390°F). Combine the spinach, mint, rind, fetta, eggs and pepper in a bowl and mix well. Set aside.
Layer 3 sheets of pastry, brushing between each layer with butter. Cut into 2x20cm rounds. Press the pastry into 2x11cm lightly greased pie tins. Repeat with the remaining pastry and 4 more tins. Fill the pastry cases with the spinach mixture and fold in the pastry edges to partially enclose. Brush the tops with butter and cook for 15–20 minutes or until golden. Makes 6.