Step 1

Cook the potatoes in boiling salted water for 10–12 minutes, until cooked through. For the final 2 minutes, add the beans and sugar-snap peas. Drain, then cool in a bowl of iced water. Drain thoroughly and transfer to a large bowl.

Step 2

Dice the avocado and add to the bowl, along with the radishes and spring onions.

Step 3

To make the dressing, put the herbs, anchovies, mayonnaise and crème fraîche in a blender (see recipe tip) and add half the lemon juice. Blitz until well combined, then taste, season with salt and pepper if necessary and add a little more lemon juice if you like.

Step 4

Stir the vegetables to mix evenly, then transfer to a large serving plate and drizzle over the dressing.