Tuna katsu sandwich: Quick, crispy and full of flavour

I know this isn’t a traditional katsu, but when it tastes this good, are you really going to complain?” says telly chef Gordon Ramsay. “While you’re at it, make double of the tonkatsu sauce. It’s the Japanese equivalent of brown or steak sauce – sweet and tangy – and it goes brilliantly with burgers, pulled pork and bacon sandwiches, as well as the Japanese classic, pork tonkatsu. It will keep for at least a week if stored in the fridge in a sealed container.”

Tuna katsu sandwich with ginger and apple slaw

Serves: 2

Ingredients:

Vegetable oil for frying

2 tbsp (heaped) plain (all-purpose) flour

1 egg

60g panko breadcrumbs

Dash of milk

2 x 170g (5.oz) thick tuna steaks

180g (6.oz) white cabbage

60g (2.oz) pickled ginger, plus a splash of the pickling liquid

4 thick slices of white bloomer loaf, crusts removed

Freshly ground black pepper

For the tonkatsu sauce:

125ml tomato ketchup

2 tbsp soy sauce

2 tbsp Worcestershire sauce

2 tbsp mirin1 garlic clove, peeled

Pinch of chilli flakes

To serve:

½ green apple (optional)

1 tsp toasted white sesame seeds or untoasted black sesame seeds (optional)

1 lime, cut into wedges

Method:

1. Place a heavy-based frying pan (skillet) over a high heat and coat the bottom of the pan with a thin layer of oil.

2. Put the flour, egg and panko breadcrumbs into three separate bowls. Season the flour with black pepper. Add a little milk to the egg and beat with a fork.

3. Dip each tuna steak in the flour, making sure it is well coated. Shake off any excess, then dip it in the egg followed by the breadcrumbs.

4. Place the steaks in the hot oil and cook for one minute on each side.

5. Meanwhile, finely slice the cabbage with a mandoline or the blade side of a box grater and combine in a bowl with the pickled ginger and pickling juice.

6. Make the tonkatsu sauce by combining the ketchup, soy sauce, Worcestershire sauce and mirin in a bowl. Grate in the garlic, add the chilli flakes and stir well.

7. To assemble each sandwich, spread the tonkatsu sauce on two slices of bread and top one of them with the cabbage slaw. Place the tuna steak on the slaw and sit the other slice of bread on top.

8. Finely slice the apple (if using) using a mandoline or sharp knife, then sprinkle with sesame seeds (if using).

9. Cut each sandwich in half and serve with the apple salad, lime wedges and any leftover tonkatsu sauce on the side.

Extracted from ‘Ramsay In 10’ by Gordon Ramsay (published by Hodder & Stoughton , £25; photography Jamie Orlando-Smith) available 14 October.