Step 1

Place custard powder and sugar in a medium saucepan and whisk in about 1/3 cup of milk to form a smooth paste. Gradually whisk in remaining milk. Slowly bring to the boil, whisking continuously, until thick. Pour into a shallow dish and cover with plastic wrap, pressing the wrap directly onto the custard to prevent a skin forming. Refrigerate for 1-2 hours until cold.

Step 2

Preheat oven to 200C. Line a large baking tray with baking paper. Remove custard from fridge and whisk in lemon curd.

Step 3

Place puff pastry sheets on lined baking tray, overlapping slightly, to form a long rectangle. Spoon custard mixture down the centre third of the pastry, leaving about 8cm at the top and bottom clear. Fold the 8cm top and bottom flaps over onto the custard. Use a sharp knife to cut horizontal strips in the pastry on either side of the custard filling, approximately 2cm in width. Fold the strips over from alternating sides to form a plait pattern, until the filling is completely enclosed. Brush liberally with beaten egg and sprinkle over sugar.

Step 4

Bake for 20-25 minutes until golden and puffed.