Add the salad potatoes to a large pan, leaving them whole. Fill the pan with water to cover the potatoes and season the water with a large pinch of salt. Bring the potatoes to a low boil and simmer for 20 mins till the potatoes are tender (a knife should easily pierce the skin).

While the potatoes cook, trim, peel and finely slice the red onion. Add the onion to a small bowl. Halve the lemon and squeeze over the juice from half. Season with a pinch of salt and scrunch together. Set the onion aside to lightly pickle.

Add the mustard to a large salad bowl. Grate in the zest from the remaining half lemon and squeeze in the juice. Drizzle in 1 tbsp olive oil. Season with a pinch of salt and pepper. Whisk to make a smooth dressing.

Trim and discard the roots and any raggedy ends off the spring onions and finely slice them. Drain the olives and add them to the salad dressing. (The olives have stones in them. Just make sure everyone knows before they tuck in – or you can stone them before adding them to the pan.)

Slice the Tenderstem broccoli on the diagonal into 4-cm long pieces. Roughly chop the parsley leaves.

When the potatoes are tender, use a slotted spoon to remove them from the boiling water. Set them aside on a chopping board to cool slightly. Add the sliced Tenderstem to the boiling water and cook them for 3 mins till bright green and just tender. Drain the Tenderstem and rinse in cold water to cool.

Add the potatoes and broccoli to the salad bowl. Stir through the pickled red onions.

Divide the salad between 2 plates. Scatter over the parsley leaves. Crumble over the feta and serve.