Preheat the oven to 180ºC. Place the potatoes in a small saucepan of cold water, bring to the boil then lower the heat and cook for 6 minutes or until soft. Drain and leave to one side.
Spray a frying pan with low calorie cooking spray and set on a medium heat. Fry the onion for 4 minutes, then add the ginger and garlic and fry for a further minute.
Add the spices, carrot and cauliflower and give the pan a stir, coating the vegetables in the spices. Add the boiling water, lime juice and tomato puree and lower to a simmer.
Cover and cook for 15 minutes until the carrots are soft and the liquid has reduced. Stir in the potatoes and peas and leave the mixture to cool slightly.
Spray a pie dish with low calorie cooking spray. Cut the filo sheets in half and layer 4 halves on top of each other in the bottom of the dish.
Spoon the vegetable mixture into the pie dish and flatten the top.
Scrunch the remaining filo sheets on top of the vegetable filling to cover completely. Spray with a little low calorie cooking spray and place in the oven for 20 minutes until lightly golden.