There are few things more versatile or more satisfying than potage parmentier (leek and potato soup) or one of its myriad variations. It’s good freshly-made and better the next day. Hot or cold, it makes a lovely start to dinner; served with some left-over meat, a great lunch. It's a great mid-afternoon pick-me-up, either straight out of the fridge or zapped in the microwave.
As delicious as is basic leek-and-potato soup, you can also include other vegetables or herbs, such as broccoli stems, asparagus stalks, a large handful of parsley or cress, etc—the variations are endless. This is one of the classic ways the French utilize left-over or less-than-perfect vegetables bought cheap from the market, a principle of both taste and economy that all would do well to adopt.
You shouldn't be a stickler about using leeks, either—while they have a more subtle flavor than onions, they can be expensive and/or difficult to source out of season. Feel free to use regular onions (the milder yellow/Spanish varieties are best) or use a couple of bunches of scallions (spring onions).
The only rub comes when it’s time to purée the soup. While it can be done in a blender, it’s much better to use a food mill. Blenders tend to make the potato starches glue-like and pulverize the woody parts of the other vegetables. The food mill doesn’t change the texture of the potato starch and strains out the vegetable pulp. It takes a little extra muscle, but it’s well worth the effort. Using the chopping blade in a food processor (Cuisinart) will also puree the soup without the potato separating provided the action is pulsed and not overdone, however the mixture should be sieved if woody-cored root vegetables such as turnips or parsnips are used. Some recipes suggest using a potato ricer (masher) which may work quite as well, since the potato and the leeks are very soft; and the result is a nicely textured soup.
This recipe makes two quarts of soup, though it's worthwhile to double or triple it; left-overs easily last 7–10 days in the refrigerator, though you’ll probably eat them long before that time.
Ingredients[edit | edit source]
- 3–4 cups (~1 lb / 450 g) sliced leeks or onions
- 3–4 cups (700–900 g / 2 lb) floury potatoes (e.g. Idaho, Maris Piper), peeled and thickly sliced
- 2 quarts (2 L) water
- 2 tbsp table salt or 1 tbsp sea/rock salt
- White pepper, freshly ground, to taste
- 4–6 tbsp heavy (double) cream
- 1–2 cups (up to 450 g / 1 lb) vegetables (optional), thinly sliced
- 1–2 handfuls flat-leaf parsley or watercress (optional), rough chopped
Procedure[edit | edit source]
- If using leeks, remove the roots and dark green leaves; wash twice as long as you think necessary to remove the grit.
- Place the vegetables, water and salt in a pot and bring to a boil. Lower the heat and gently simmer (partially covered) for 45–50 minutes. The soup is done when you can easily mash the vegetables against the side of the pot.
- Puree the soup using a food mill fitted with the fine disc. Optionally, pulse it in a blender just until smooth and pass through a fine sieve.
- Chill the soup if it is to be served cold, or gently reheat it to a simmer. Refrigerate any left-overs. It will keep for days if refrigerated in a covered container as soon as it cools.
- Add 1½–2 tsp cream (or whole milk) per portion just before serving. You’ll need more cream if you’re serving the soup hot or if it’s a bit watery; the idea is to create a smooth, silky puree, but you don’t want the taste or mouth feel of the cream to predominate. Taste and adjust for salt and pepper.
Notes, tips, and variations[edit | edit source]
- After cooking the soup, leave it to cool in the refrigerator for 1–2 hours. It will taste better when heated up to serve!
- Raw vegetables should be added to the soup at the beginning of the cooking time; if using left-over vegetables or herbs, add them after the soup has been cooking for 30–40 minutes, so they cook just long enough to completely warm through.
- If using "regular" table salt instead of kosher salt, reduce the amount of salt to 1–1½ tbsp. A chilled soup usually requires slightly more seasoning than that added to a hot serving; this can be added individually to taste.
- A combination of young buttery parsnips and a couple of punnets of mustard-and-cress makes the classic French puree pasternak. A teaspoon of potato, rice, or corn starch should be used to stabilise the puree, which should be milled or sieved.
- Using white pepper is preferable for color. Use fresh-ground black pepper otherwise.
- A proportion of light chicken or vegetable stock may be used instead of the water.
- Snipped chives are the classic garnish for leek-and-potato soup. When including asparagus, you can use steamed asparagus tips as a garnish; with broccoli, use steamed broccoli florets—you get the idea. Of course, if you’re just pouring a mid-afternoon mug for yourself, who cares how it looks?