Soups use everything in this course: stocks, thickeners, purées and emulsions. Cooks group them by how they look.
Key idea
Clear soups: broth (simmered meat), and consommé, a stock clarified with a "raft" of ground meat, egg whites and mirepoix that traps tiny particles. Thick soups: cream soups (thickened with roux or a liaison and finished with cream), purées (thickened by the vegetables or beans themselves, such as potato-leek or split pea), and bisques (shellfish soups, often thickened with rice). Specialty and cold soups include gazpacho and vichyssoise.
- Sweat aromatics gently; build flavor before the liquid.
- Purée soups smooth, then pass through a sieve for a restaurant finish.
- Season at the end, and taste hot (cold soups need more salt).
- Garnish to add texture: croutons, herb oil, a spoon of cream.
Safety
- Blend hot soup in small batches, no more than about half full, with the blender's vent open and covered with a towel, or use an immersion blender in the pot.
- Cool large batches of soup by the two-stage rule in shallow pans or an ice bath.
Why it works
A purée is thick without flour because cooked starchy vegetables (potato, beans, squash) release their starch when blended. Too much blending of potato soup in a powerful blender can make it gluey, for the same reason as mashed potatoes.
Worked example: Name the soup
Potatoes and leeks simmered in stock, then blended.
- Thickened by the potatoes themselves.
Answer: A purée soup (potage Parmentier).
Common mistake
Boiling a cream soup after the cream or liaison goes in. It can curdle or scorch.
Practice at home
- Make potato-leek soup. Serve half hot as potage Parmentier, and chill the rest with cream for vichyssoise, tasting for salt when cold.
In Meal Prep
- Potato and Leek Soup (Potage Parmentier): from Escoffier
- Lobster Newberg: a rich cream sauce from Delmonico's, kin to a bisque