Korokke Pan (コロッケパン, croquette roll)

Ingredients

Equipment Needed

• •Heavy pot or deep skillet for frying
• •Frying thermometer
• •Wire rack set over a tray
• •Three shallow dishes for breading

Instructions

1. 1

   Cook the potatoes

   Put the potatoes in a pot, cover with cold water, and simmer until a skewer slides through without resistance, about 20 minutes. Starting in cold water cooks them evenly from edge to center. Drain, peel while hot if needed, and return them to the warm pot for a minute so surface moisture escapes.

   Dry potato is the detail that decides the filling. Too much water makes the korokke heavy and softens the crust from the inside.
2. 2

   Season the onion

   Warm 1 tablespoon oil in a skillet and cook the onion over medium heat until soft and lightly golden, 6 to 8 minutes. Add the soy sauce and sugar, and cook until the pan looks nearly dry. This takes the raw bite out of the onion and gives the potato a quiet savory base without making the filling wet.

3. 3

   Mash and shape

   Mash the hot potatoes roughly, leaving a few small pieces so the center doesn't become paste. Fold in the onion, salt, white pepper, and 2 tablespoons flour. Shape into 4 oval patties about the length of the rolls, then chill for 10 minutes. Cooling firms the starch so the patties hold their shape in the oil.

   Shape the korokke a little flatter than you think. A thick one browns before the center warms through, and a flat oval sits neatly in the bread.
4. 4

   Bread the korokke

   Set out flour, beaten egg, and panko in three shallow dishes. Coat each patty lightly in flour, dip in egg, then press into panko until covered all over. The flour helps the egg cling, and the egg gives the panko something to hold, so the crust stays attached instead of floating away in the oil.

5. 5

   Fry until crisp

   Heat 2 inches of oil to 175 C. Fry the korokke in batches until deep golden and crisp, about 2 minutes per side. The filling is already cooked, so you're setting the crust, not cooking the center from raw. Drain on a rack, not paper, so the underside stays crisp.

   If the oil is too cool, the panko drinks oil before it browns. If it's too hot, the crust darkens while the inside stays cold. Listen for a steady, lively fry.
6. 6

   Build the rolls

   Split the koppepan lengthwise without cutting all the way through. Brush the inside with tonkatsu sauce, add a small bed of shredded cabbage, and tuck in one hot korokke. Spoon a little more sauce over the top. The cabbage keeps the crust from sitting directly against the bread and gives a clean crunch against the creamy potato.

7. 7

   Serve at once

   Serve the rolls while the korokke is still crisp and the sauce has just begun to soak into the bread. Add Japanese mustard if you like its heat, but keep it light. This sandwich is about contrast: soft roll, sharp sauce, crisp panko, creamy center.

Chef Tips

• •Use a floury potato, not a waxy one. Russet works well outside Japan, and danshaku is the old Japanese choice. The right potato gives you a creamy center without turning gluey.
• •Panko matters here. Its coarse flakes make the loose, crisp shell that korokke needs. Fine breadcrumbs give a denser crust and the bread roll will flatten it quickly.
• •A soft hot dog roll is a sensible stand-in for koppepan, as long as it is plain and tender. A crusty roll changes the dish into something else.
• •Don't drown the korokke in tonkatsu sauce. Brush, then finish with a spoonful. The sauce should season the bread and crust, not hide the potato.

Advance Preparation

• •The potato filling can be shaped up to one day ahead and kept covered in the refrigerator. Bread the patties just before frying so the panko stays dry.
• •Fried korokke are best the day they are made. To re-crisp leftovers, warm them on a rack in a 200 C oven for 8 to 10 minutes, then build the rolls.

Frequently Asked Questions

Nutrition Information

1 serving (about 290g)