Cream of Leek Soup

This is a cream of leek soup built the old-fashioned way, with a proper roux as the thickening base rather than a pureed potato shortcut. Half a pound of butter and a full cup of flour cook together for several minutes before chicken stock streams in, creating a rich, glossy bisque-style sauce that wraps around tender steamed leeks.

Steaming the leeks separately rather than cooking them in the soup is a smart call. They retain their delicate sweet onion flavor instead of turning aggressive, and reserving the steaming water (don’t drain) means none of that leek essence gets lost. It goes back into the soup along with the leeks themselves.

Using half and half rather than heavy cream gives you a soup that’s still rich and luxurious without crossing into too-thick territory. The do-not-boil rule once the cream goes in is critical, since boiling cream-based soups can cause them to break or curdle.

Chef Tips

• Wash leeks very thoroughly. Slit lengthwise and rinse between layers under running water. Grit hides deep in the green parts.
• Cook the roux for the full 2 to 4 minutes. Raw flour taste in cream soups is unforgivable.
• Add the cream gradually while stirring constantly. Dumping it in cold causes the soup to seize and lump.
• For a smoother soup, blend half the leeks before adding back. Pureed leeks add body without losing the chunky character.

Variations

• Add 1 cup of diced cooked ham and 1 cup of diced cooked potatoes for a hearty meal-in-a-bowl as the recipe suggests.
• Substitute heavy cream for half and half for a richer, restaurant-style version.
• Garnish with crumbled bacon, snipped chives, and a swirl of cream for restaurant-style presentation.