For the filling
1.25 kg large waxy potatoes, halved
85g butter
2 onions, chopped
1 tbsp black mustard seed
2 tbsp finely chopped ginger
2 red chilies, halved, deseeded and sliced
1 tbsp tomato paste
2 tsp ground cumin
1 tsp ground coriander seed
1/2 tsp turmeric
1/2 tsp garam masala
400g bag fresh spinach
4 tomatoes, chopped
small bunch coriander, chopped
For the pastry
270g pack filo pastry (6 large sheets)
50g melted butter
1/2 tsp poppy seeds seed
Method
Heat oven to 190C/170C fan/gas 5.
To make the filling, heat a pan of salted water. When boiling, add potatoes and boil for 15 mins until tender.
Melt the butter then fry the onions for a few mins. Combine tomato paste, spices and some water. Add spice paste, mustard seeds, ginger and chilies and fry, stirring occasionally, for about 7 mins until soft.
Wilt the spinach by immersing in boiling water. Drain and squeeze out as much liquid as you can, then chop it.
Drain the potatoes and crush lightly to break them up into chunks rather than mash. Toss in the spice mixture with plenty of salt to coat them, then add the spinach, tomatoes and coriander.
Carefully unroll the pastry and brush 2 x 20cm loose-bottomed sandwich tins with some butter. Brush the first sheet of pastry and lay it in and across the tin so that it hangs over the side. Do the same with another sheet of pastry to cover the other side of the tin (so the two form a cross), butter and fold the final sheet in half and lay it in the base of the tin to create a firm base. Do the same with the other tin and remaining pastry.
Spoon the filling into the tin and fold up the pastry that is overhanging so that it covers the filling. Brush generously with the remaining butter and sprinkle with seeds. Bake for 35 mins until golden and crisp.