Double-Fried Hire Katsu Sando with House Sauce

Method

1. Start with the sauce. Put the ketchup, Worcestershire sauce, soy sauce and honey in a 14 cm saucepan and simmer on low heat, stirring, for 2 min. When it is glossy and coats the back of a spoon, turn off the heat and let it cool; it thickens further as it cools.

   Add in this stepKetchup 2 tbspWorcestershire sauce 2 tbspSoy sauce 1 tspHoney 1 tsp

   low heat

2. Peel off the thin silvery membrane from the fillet with a knife and cut into 3 cm-thick medallions. Press each to an even 2.5 cm with your palm and trim the sides slightly so they sit snugly side by side on the bread. Season with salt and pepper, leave for 10 min, then pat away any moisture that has appeared.

   Add in this stepPork fillet (tenderloin), in one piece 260 gSalt 2 pinchBlack pepper 1 pinch

3. Whisk the egg, milk and about half the flour into a thick egg batter. Dust the pork thinly with the rest of the flour and shake off the excess, coat in the batter, then press on the breadcrumbs firmly. Leave on a rack for 5 min so the coating sets and won't slip off in the oil.

   Add in this stepPlain flour 3 tbspEgg 1Milk 1 tbspFresh breadcrumbs or panko, rubbed finer 55 g

4. Pour oil 4 cm deep into a 22 cm pot and heat on medium-high heat for about 9 min to 160 °C. A crumb dropped in should sink close to the bottom and then rise slowly.

   Add in this stepNeutral oil for frying 900 ml

   medium-high heat

5. Slide the pork in gently, away from you, frying in 1 batch. Fry on medium heat, holding the oil at 160 °C, for 4 min. When the crust is pale golden, lift it out and stand it on a rack to rest for 4 min; meanwhile the residual heat gently cooks the centre.

   medium heat

6. Turn the heat up to medium-high heat and bring the oil to 180 °C, then refry in the same batches for 1 min each until deep golden and crisp. Rest on the rack for 2 minutes. It is ready when the centre reaches at least 63 °C; at that point fillet stays juicy with a faint blush of pink.

   medium-high heat

7. Mix the soft butter with the mustard and spread it on one side of each slice, right to the edges. Dip the katsu in the sauce on both sides, line the pieces up tightly on a buttered slice and close with a second slice. Wrap tightly in cling film and weigh down with a plate for 10 min.

   Add in this stepSoft white sandwich bread (shokupan), 1.5–2 cm slices 4Butter, softened 15 gJapanese mustard (karashi) or Dijon 1 tsp

8. Warm a bread knife in hot water and dry it, trim off the crusts, then cut into three so the cross-section of the meat shows. Wipe the knife between cuts for clean edges.