Roast Tuna Loin with Potato Tartine and Citrus Sauce

A tangy citrus sauce sets off peppered tuna loin in Paul Bloxham's flavourful contemporary fish recipe
By Paul Bloxham
Roast Tuna Loin with Potato Tartine and Citrus Sauce
  • Rating:
  • Serves: 4
  • Cook Time: 15 minutes
  • Prep Time: 20 minutes
  • Effort: medium



  • 25 g butter
  • 2 tbsp olive oil
  • 3 potatoes, peeled and thinly sliced into even-sized circles
  • 800 g tuna steaks
  • 3 tbsp black peppercorns, freshly cracked
  • 2 tbsp finely grated parmesan
  • black pepper
  • 4 bok choy
  • 3 tbsp tamari soy sauce
  • grated zest of 1 lemons
  • 1 tbsp freshly squeezed lemon juice
  • grated zest of 1 limes
  • 1 tbsp fresh lime juice
  • 1 tsp freshly grated ginger
  • 2 tbsp fish stock
  • 1 tomato, skinned and diced
  • 1 tbsp chopped coriander
  • 1 tbsp extra virgin olive oil


1. Preheat the oven to 200ºC/gas 6.

2. Meanwhile heat the butter and 1 tablespoon of olive oil in 4 small blini or Yorkshire pudding tins. Add the potato slices, overlapping them to form a flower shape in each tin. Bake the potato tartines in the oven until golden-brown, around 15 minutes. Sprinkle with Parmesan and bake for a further 1-2 minutes until the cheese has melted.

3. Meanwhile, heat a ribbed griddle pan until very hot. Roll the tuna loin in the cracked peppercorns, then rub with the remaining olive oil.

4. Cook the tuna on the griddle until a crust has formed on all sides. Transfer the tuna to a roasting tray and roast, alongside the potato tartines, for 6 minutes until medium rare.

5. Meanwhile, bring a saucepan of salted water to the boil. Add the bok choi and cook for 2 minutes. Drain.

6. In a small saucepan, gently heat together the soy sauce, lemon zest and juice, lime juice and zest, ginger, fish stock, tomato, coriander and extra-virgin olive oil. Season with salt and freshly ground pepper.

7. To serve, slice the tuna and divide among 4 serving plates. Serve with the potato tartines, bok choi and the citrus sauce.

Rate This Recipe