- Prepare your choice of Japanese curry the day before. Ensure the meat, vegetables or potatoes used in the curry are cut into small pieces. Refrigerate overnight to create a solid and pasty texture.
- Take the Japanese curry out from the refrigerator and bring to room temperature. Also bring unsalted butter to room temperature.
- Place bread flour, cake flour, salt and sugar into a large mixing bowl. Whisk until combined. Add instant dry yeast and pour in warm milk. Combine until a rough dough forms then, shape the dough into a ball. Add butter on top and knead the dough until there is no big pieces of butter left. Place the dough on a lightly floured worktop and continue to knead until it’s smooth. Form into a ball and put it into a bowl. Cling wrap and leave to proof until doubled in size. To test the dough if it’s ready, dust your finger with flour and poke the centre of the dough. The dough is ready if the hole does not close up.
- Lightly dust your worktop with flour and place the dough on top. Gently press the dough down and fold it into thirds, width wise. Then, fold the dough again into thirds, length wise. Flip the dough so that the seam is facing down. Twist the dough to form a smooth ball.
- Weigh the dough on a kitchen scale and divide the weight by 8. Cut the dough into 8 equal pieces and weigh each piece. Cut off extra dough it if weighs more than the calculated figure and add more dough if it weighs less. Roll each dough into a rough ball and place them on a baking tray lined with parchment paper. Cover with cling wrap and allow to sit for 15 mins at room temperature.
- Put seam side of the dough facing upwards. Flatten the dough with your palm and fold it in thirds, width wise. Then, fold in thirds length wise. Flip the dough around so that the seam side is facing down. Flatten again and turn the dough upside down so the seam side is up. Using a rolling pin, roll into a 9cm circle and place on a baking tray lined with parchment paper. Repeat with all dough balls. Cover them with cling wrap and allow to sit for 10 mins.
- Press the edges of the dough with your fingers to thin the dough out. The centre should be thicker than the edges. Each dough should be roughly 10cm in diameter. With the seam side facing upwards, scoop about 1½ tbsp curry paste in the middle of the dough. Fold the dough into half, ensuring no curry paste touches the edges. Pinch the edges tightly to seal properly. Fold the pinched edges and press again to secure. Place the wrapped dough seam side down on the baking tray lined with parchment paper and cover with a damp tea towel. Repeat with remaining dough and curry paste.
- Pour panko into a shallow tray and prepare a beaten egg. Brush egg over the dough, coat with panko and place it back to the lined baking tray. Repeat with remaining formed dough. Cover with cling wrap and leave to rise until 1½ times in size.
- Heat enough oil for deep frying in a pot. Carefully place the curry buns, seam side down, for 5 secs before turning them around. Continuously flip them around to deep fry until they are golden brown. Drain and continue to fry remaining curry buns.
- Serve hot or warm.