Put the sausagemeat in a bowl and add the cumin, coriander, fennel seeds, paprika, garlic, spring onions and a little salt and pepper. Mix well with your hands until evenly combined.
Roll out the pastry thinly on a lightly floured surface to a 40 cm (16 inch) square, then cut into 4 strips. Divide the pork mixture into 4 pieces and pinch out a quarter of the sausagemeat along the centre of each strip.
Brush the pastry edges with a little beaten egg and fold one side of the pastry over the sausagemeat, pressing the edges of the pastry firmly together to make long, thin logs. Brush with beaten egg and cut into 5 cm (2 inch) lengths. Place on a large greased baking sheet and score 2 or 3 cuts along the top of each with a sharp knife.
Bake in a preheated oven, 220°C (425°F), Gas Mark 7, for 15 minutes. Reduce the temperature to 160°C (325°F), Gas Mark 3, and cook for a further 10–15 minutes until deep golden and cooked through.