Preheat the oven to 200°C / 400°F / Gas mark 6.
Line a baking tray with greaseproof paper and set aside.
Using a large frying pan, heat 1 tablespoon of the oil and cook the potatoes and onion for about 10 minutes until golden and tender. This may need to be done in batches.
Season with salt and pepper, then set aside.
Heat the remaining oil in the pan. Add half the cabbage, garlic, cumin seeds, chilli, seasoning and 1 tablespoon of water and cook for about 5 minutes or until the cabbage is wilted and tender.
Remove from the pan and repeat with the remaining ingredients.
Roll out half the pastry along with the toasted cumin seeds to incorporate and line a 20cm pie plate with the pastry.
Place the potatoes and onions in the bottom, then top with the cabbage mixture.
Crack 4 eggs over the cabbage mixture in 4 different locations.
Brush the border with water.
Roll out remaining pastry, then cover, trimming the edges and pinching together to seal.
Brush the pastry with milk.
Make a hole in the centre.
Place on the baking tray and cook for 25-35 minutes until crisp and golden.