Why This Soup Deserves a Permanent Spot in Your Repertoire

Leek and potato soup is one of those quiet British classics that never quite gets the fanfare it deserves. It costs very little, it asks almost nothing of you in terms of technique, and yet the result is silky, comforting and deeply savoury in a way that a tinned soup can never manage. Made properly — leeks softened gently in butter rather than fried, floury potatoes cooked until they collapse, a generous handful of chives at the end — it is the kind of bowl you want on a cold Tuesday in February, with a slice of buttered soda bread alongside.

This version sits somewhere between a potage and a proper blended soup. It is smooth but not watery, lightly thickened with a spoonful of flour so it holds its body, and finished with just enough cream to make it feel indulgent without tipping into richness. Everything below is written for a standard 2-litre pan and serves four to six comfortably.

What You Will Need

• 3 large leeks (roughly 500g once trimmed), white and pale green parts only
• 50g unsalted butter, plus a little extra for serving
• 1 tbsp plain flour
• 700g floury potatoes — Maris Piper, King Edward or Desiree
• 1.2 litres good chicken or vegetable stock
• 1 bay leaf and a few sprigs of thyme, tied together if you have string
• 150ml double cream (optional but recommended)
• A small bunch of fresh chives
• Salt, white pepper and a scraping of nutmeg

A word on the potatoes: floury varieties break down as they cook, which is exactly what you want here. Waxy potatoes will give you a gluey, stubborn soup that never quite blends smooth, so save those for your salads.

Preparing the Leeks Properly

Leeks are the backbone of this soup, so it is worth spending two extra minutes on them. Trim away the root and the tough dark green tops, leaving the white and the softer pale green section. Slice each leek in half lengthways, then fan the layers open under a running tap — grit loves to hide between them, and a single gritty mouthful will ruin an otherwise lovely bowl. Shake dry and slice thinly across the width.

Melt the butter in a heavy-based pan over a low to medium heat. Add the leeks with a good pinch of salt, stir to coat, then cover and let them sweat for eight to ten minutes. You are not looking for colour here — a little gold at the edges is fine, but browning will make the finished soup taste sweeter and less clean. The leeks should be completely soft and glossy, reduced to perhaps a third of their original volume.

Building the Soup

Sprinkle the flour over the softened leeks and stir constantly for a minute. This brief cooking takes the raw taste out of the flour and gives the soup its gentle thickness. Pour in the stock gradually, stirring as you go to avoid lumps, then add the potatoes, cut into rough 2cm chunks, along with the bay leaf and thyme.

Bring everything up to a bare simmer, then turn the heat down low and cook uncovered for about twenty minutes, until a potato chunk crumbles easily against the side of the pan. Resist a rolling boil — it will break the potatoes apart unevenly and dull the flavour of the leeks. Fish out the bay and thyme stems, then blend. An immersion blender is easiest; if you are using a jug blender, work in batches and never fill it more than halfway, as hot soup expands dramatically.

For a really velvety result, push the blended soup through a fine sieve with the back of a ladle. It takes five minutes and turns a good soup into a restaurant one. If you prefer a little texture, blend only two-thirds and stir the rest back in.

Finishing with Cream and Chives

Return the soup to a low heat and stir in the cream, if using. Season carefully with salt, a little white pepper — black pepper will speckle the pale green — and the faintest grating of nutmeg, which lifts the whole thing without announcing itself. Taste again; potato soups usually need more salt than you expect.

Chives are not a garnish here, they are part of the recipe. Snip them finely with scissors rather than chopping with a knife, which bruises them and turns them dark. Stir half through the soup just before serving and scatter the rest over the top, along with a small knob of butter that will melt into glossy pools as it hits the bowl.

Getting Ahead, Freezing and Ringing the Changes

The soup keeps beautifully in the fridge for three days and freezes well for up to three months — though add the cream and chives after reheating, not before. Reheat gently, loosening with a splash of stock or milk if it has thickened overnight.

Once you have the base mastered, it invites tinkering. A handful of watercress blended in at the end gives a peppery edge; a teaspoon of grain mustard stirred through adds warmth; a few rashers of streaky bacon, fried crisp and crumbled over the top, turn it into something altogether more substantial. In summer, serve it chilled as a vichyssoise with an extra squeeze of chives. Whatever the season, it is the sort of cooking that reminds you why simple British food, done well, is so hard to beat.