Instructions
1 Spray a large non-stick frying pan (which has a lid) with olive oil and set over medium heat. Add onion, garlic and celery. Cook, stirring occasionally, for 3 minutes, or until fragrant.
2 Increase heat to medium-high. Add lamb mince to pan and cook, stirring with a wooden spoon to break up mince, for 5 minutes, or until browned. Stir tomato paste into mince and cook for 1 minute.
3 Add kumara, tomatoes and beef stock to pan. Cover and bring to the boil. Reduce heat. Simmer mixture for 20 minutes, or until kumara is tender. Stir baby spinach and peas into mixture and cook until spinach wilts. Leave mixture to cool slightly.
4 Preheat oven to 200°C. Spray 4 x 1 1/2-cup capacity (10cm wide) heatproof dishes or bowls with olive oil. Spoon lamb mixture into dishes. Lay pastry sheet on a work surface to thaw, then cut out 4 x 12cm rounds. Top pie filling in each dish with a pastry round, pressing excess pastry over edge. Use a sharp knife to score centre of each pastry lid with two small slits and brush lightly with milk.
5 Bake pies for 20-25 minutes, or until pastry is puffed and golden, then serve with salad leaves tossed with vinaigrette.