Preheat the oven to 180C. In a frying pan heat the oil and sauté the onion and garlic for 5 minutes or until they become soft. Add the tomatoes, capers, olives, cubed potatoes and cauliflower florets. Add the lampuki pieces and cook until the lampuki meat has changed colour and tender. Season with salt and pepper. Once ready, set aside and let the mixture cool down. Grease a baking tray using some butter, and open up the pastry. Place pastry on bottom of the tray and fill in with lampuki mix. Cover with the other pastry. Seal the edges together. Glaze the top with a beaten egg and bake for 45minutes, the pie has turned golden and cooked from both sides.