Boil the eggs to perfection: Place the eggs in a single layer in a saucepan and cover with cold water by about 2.5cm. Bring to a rolling boil over high heat — you'll see large bubbles breaking the surface and steam rising steadily. Once boiling, cover the pan, remove from heat, and let sit for exactly 10 minutes. The yolks will be fully set with a creamy, pale yellow centre, not chalky.

Ice bath shock: While the eggs sit, fill a large bowl with cold water and a handful of ice cubes. After 10 minutes, transfer the eggs to the ice bath using a slotted spoon. You'll hear a satisfying sizzle as the hot shells hit the cold water. Let them cool for 5 minutes — this stops the cooking and makes peeling effortless.

Peel with patience: Gently tap each egg on the counter to crack the shell all over, then roll it between your palms. Start peeling from the wider end where the air pocket sits; the shell should come away in large pieces. The peeled eggs will be smooth and bouncy to the touch, with no rubbery white patches.

Chop the eggs: Place the peeled eggs on a cutting board and use a sharp knife to cut them into roughly 1cm chunks. You want a mixture of textures — some larger pieces for bite, some smaller bits that melt into the dressing. The yolks should crumble slightly as you cut, releasing a faint, savoury aroma.

Build the dressing: In a large mixing bowl, whisk together the mayonnaise, Dijon mustard, lemon juice, salt, and pepper until smooth and pale yellow. The mixture should smell tangy and rich, with the mustard cutting through the creaminess. Taste and adjust seasoning — it should be slightly punchy because it will mellow when mixed with the eggs.

Combine everything: Add the chopped eggs, spring onions, celery, chives, and capers (if using) to the dressing. Fold gently with a rubber spatula until every piece is coated. The final mixture should look glossy and cohesive, with flecks of green throughout. You'll see the celery and onions suspended evenly, not clumped together.

Prepare the lettuce cups: Wash and thoroughly dry the lettuce leaves — any water left on them will make the cups soggy. Pat them dry with a clean tea towel until they feel crisp and cool. Trim any thick stem ends so the leaves sit flat, like little boats ready to be filled.

Assemble and serve: Spoon about 2 tablespoons of egg salad into each lettuce cup, mounding it slightly in the centre. The leaves should cradle the filling without splitting. Serve immediately, or store components separately for meal prep. The cups should look vibrant, with the green lettuce contrasting against the creamy yellow filling.