Three-Bean Mediterranean Tuna Salad with Lemon-Dijon Vinaigrette

Method

1. Step 1: Bring a large pot of well-salted water to a rolling boil. Drop in the trimmed green beans and blanch for 3 minutes — they should still squeak between your teeth when bitten, not soften, and their colour should shift from dull olive to vivid jade. Lift them straight into a bowl of iced water for 2 minutes to lock that chlorophyll, then drain, pat completely dry on a tea towel, and cut into 3cm lengths. Wet beans will water down your dressing.

2. Step 2: While the water heats, toss the sliced red onion with 1 tbsp of the red wine vinegar and a pinch of salt in a small bowl. Leave for 10 minutes; the harsh sulphur bite mellows and the slices turn a translucent pink. Drain before using and discard the vinegar.

3. Step 3: Make the vinaigrette. In a jam jar or small bowl, whisk the lemon juice, the remaining 1 tbsp vinegar, Dijon, grated garlic, oregano, 1/2 tsp salt and black pepper. Add the olive oil in a thin stream while whisking hard — the mixture turns cloudy and thickens slightly as it emulsifies. Taste it: it should be sharp and bright, not flat.

4. Step 4: Tip the cannellini beans and chickpeas into a colander and rinse under cold running water for 30 seconds. This washes off the starchy canning liquid that would otherwise dull the dressing. Shake well, then spread on a tea towel and blot dry.

5. Step 5: Drain the tuna and flake it into roughly 2cm chunks with a fork. Resist the urge to mash it to a paste — those larger pieces give the salad structure and let you taste the fish rather than just salt.

6. Step 6: In a large bowl, combine the cannellini, chickpeas, green beans, cherry tomatoes, cucumber, olives, capers and drained pickled onion. Pour over the vinaigrette and fold gently with a rubber spatula, lifting from the bottom, for about 20 seconds — everything should be coated without the beans getting crushed.

7. Step 7: Fold in the tuna last, just three or four turns, so the chunks stay intact. Let the salad sit at room temperature for 15 minutes; the beans absorb the dressing and the flavours knit together.

8. Step 8: Taste and adjust — a squeeze more lemon if it tastes flat, a pinch more salt if it tastes thin. Scatter over the crumbled feta and chopped parsley and serve.