Soak the onion. Place the diced red onion in a small bowl of cold water and leave it for 10 minutes while you prepare everything else. You'll notice the sharp, eye-watering bite mellow into something sweeter and gentler. Drain well before using.

Make the dressing. In a small jar, combine the olive oil, lime juice, red wine vinegar, cumin, smoked paprika, salt, and pepper. Screw the lid on tightly and shake hard for about 20 seconds until the mixture turns a deep, cloudy amber and emulsifies. Give it a sniff — it should smell bright, citrusy, and faintly smoky.

Combine the base ingredients. In your large salad bowl, add the drained black beans, cherry tomatoes, sweetcorn, diced red pepper, drained onion, and jalapeño if using. Toss gently with a spoon until everything is evenly distributed and the colours look bright and inviting.

Dress and rest. Pour the dressing over the bean mixture and toss well. You'll see the beans darken slightly as they absorb the dressing. Let this sit for 5 minutes — this brief rest lets the flavours marry, and the tomatoes release a little juice that loosens everything beautifully.

Fold in the avocado. Add the diced avocado and fold it through with a light hand, just until it's distributed. The avocado should stay in distinct chunks rather than mash into the dressing. If it smears, you've been too rough — next time use a gentler folding motion.

Finish with coriander and taste. Scatter the chopped coriander over the top and give everything one final gentle toss. Taste a spoonful — you're looking for a balance of creamy, tangy, and fresh. Add a pinch more salt or a squeeze of lime if it tastes dull.

Serve immediately. Transfer to individual bowls or set the whole thing in the middle of the table with salad servers. The avocado is at its best within 30 minutes, while the edges are still clean and green.