Recipe courtesy of Psychologies Magazine (Spring 2018 edition).  Recipe taken from Feasting by Amanda Ruben.  

This more sophisticated version of your average tuna salad is a great dish for entertaining.  The rest of the salad can be assembled a few hours ahead, but leave the tuna and poached eggs until last to make it restaurant quality.

Serves:  8-10

Ingredients:
250g green beans, trimmed, 300g Kipfler (finger) potatoes, 60ml olive oil, plus extra for the tuna, 80ml vinegar, 4 eggs, 600g yellowfin tuna fillets, 2 tbsp Dijon mustard, 12 baby cos lettuce leaves, 200g vine-ripened cherry tomatoes, halved, Squeeze of lemon, Dill sprigs, to garnish, Edible flowers, to garnish (optional)

Black Olive Tapenade Dressing:
80g black Kalamata olives, pitted and diced, 1 tbsp capers in brine, drained and diced, 20g flat-leaf parsley, finely shredded, ¼ red chilli, seeded and finely diced, Juice of ½ lemon, 1 ½ tbsp olive oil

Tuna Mayonnaise:
500g mayonnaise, 200g tinned tuna, drained, 1 tbsp capers in brine, drained, Juice of ½ lemon, 4 anchovy fillets

Tuna Spice Mix:
1 tsp fennel seeds, freshly ground, 1 tsp coriander seeds, freshly ground

Method:

1. Fill a saucepan with 2 litres of water and bring to the boil.  Blanch the beans for 90 seconds, then drain and refresh in cold water.  Drain again, then transfer to a plate lined with paper towels.  Put the potatoes in a saucepan and cover with cold water.  Add a pinch of salt, then bring to the boil.  Reduce the heat and simmer for 12-15 minutes, until cooked.  Drain the potatoes, then peel and cut into slices while warm.
2. Heat 2 tablespoons of oil in a large non-stick frying pan over a high heat.  Fry the potatoes in batches, adding more oil as needed, until brown and crispy on both sides.  Drain on paper towels.
3. Cut the tuna fillet into three pieces and rub with olive oil, then season with salt and pepper.  Heat 2 tablespoons of oil in a large non-stick frying pan over a high heat and sear the tuna for about 20 seconds on each side.  Set aside to cool.
4. Make the tapenade dressing by mixing all the ingredients in a bowl.  For the tuna mayo, blend the ingredients in a food processor until smooth.
5. Brush the tuna pieces with the mustard and roll in a bowl with the combined spice mix.  Slice into 1.5cm pieces.  Bring a saucepan of water to the boil, then add the vinegar.  Reduce the heat to simmer, give the water a swirl and crack in the eggs one at a time.  Cook for 3 minutes.  Remove with a slotted spoon.  Rest on paper towels
6. To assemble, arrange some cos leaves on a plate and top with one third of the sliced tuna, beans, potatoes, tomatoes and tapenade.  Repeat with two more layers, finishing with spoonfuls of tapenade, lemon juice and the dill sprigs.  Top with eggs and edible flowers if using.  Serve with the tuna mayonnaise.