Gurdeep Loyal's Thai Fish Pie with Crispy Turmeric Potatoes

1. Dry-toast the coconut in a frying pan over a medium-low heat for 2-3 minutes until it turns golden brown but not burnt, then tip onto a plate to cool completely.

2. Next, make a paste in a small grinder or blender by whizzing together the lemongrass, galangal, lime juice and zest and 1½ teaspoons of salt - add a splash of water if needed. Pour into a bowl, then whisk through the Thai green paste and fish sauce.

3. Add the fish pie mix, prawns, toasted coconut and diced celery. Stir well, then pour into the base of a deep-sided 18 x 22cm (7 x 8½in) pie dish or equivalent. Preheat the oven to 180'C fan/200°C/400°F/Gas mark 6.

4. Meanwhile, use a mandoline or very sharp knife to slice the potatoes into very thin round discs 1.5-2mm (¼in) thick, then set aside.

5. Next, in a large jug whisk together the coconut milk, cornflour, and a pinch of sugar, until fully combined. Pour over the fish and prawns in the pie dish, then scatter the chopped Thai basil on top. Layer the potato slices on top, overlapping into a spiral design to cover the filling completely.

6. Melt the butter in a saucepan along with the turmeric, nigella seeds and a pinch of salt, whisking well. Brush all the turmeric butter over the top of the potatoes.

7. Place the fish pie on a baking tray to catch any spillage and bake for 35-40 minutes until cooked through and crispy golden on top. Cover with foil if the top is browning too quickly and, if you like it extra-crispy, finish under a hot grill for 3-5 minutes.

8. Remove from the oven and rest 10 minutes before diving in. Serve with a green salad.