Why it works: Pepper and lemon match in chemistry and in kitchens. They rank in the top 3% of all ingredient pairs, and cooks put them together in 27,047 recipes. Both carry trans-2-nonenal, which smells cardboard, fatty. The science ↓
Black Bean Soup
Ingredients
Directions
Prepare the beans
Wash the beans in cold water and soak overnight.
Drain the beans and place them in a soup kettle with boiling water. If using beef, add it now.
Cover and simmer gently for two hours.
Add another pint of boiling water and press the mixture through a puree sieve.
Finish the soup
Wash the kettle, return the soup to it, and bring to a boil. Season with salt and pepper.
If the soup is too thick, add enough water to achieve the desired consistency.
Stir in the grated onion.
Serve
Pour the soup into a tureen over sliced hard-boiled eggs and sliced lemon.
If using wine, add it and serve immediately.
Transcribed from a scanned cookbook and modernised for today's kitchens. Where the book gave no heat or time, or said "a moderate oven", the temperatures and times here may be modern equivalents rather than the book's own figures.
Explore the science
The flavor team
The pairs that carry this dish. Each one is judged two ways: how much their aromas overlap, and how often cooks already put them together.
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Pepper + lemontop 3% of all pairsSmell alikestrongCooked together27,047 recipes
Shared aroma: trans-2-nonenal (cardboard, fatty).
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Beef + oniontop 7% of all pairsSmell alikemoderateCooked together17,092 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Beans + oniontop 7% of all pairsSmell alikestrongCooked together5,242 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Beef + peppertop 10% of all pairsSmell alikemoderateCooked together18,971 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Beans + peppertop 11% of all pairsSmell alikemoderateCooked together4,733 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Black turtle beans
- Form the main body and thick, earthy texture of the soup once pureed.
- Stock or lean beef
- Adds savory depth and body to the soup's flavor.
- Grated onion
- Adds aromatic sharpness and flavor to the finished soup.
- Wine
- Adds acidity and aroma when stirred in just before serving.
The step that matters
Pressing the mixture through a puree sieve. Pureeing the cooked beans breaks down their starchy cell walls, creating a smooth, body-rich soup. Incomplete pressing leaves a grainy texture.
Swap the onion
How well each one fits the dish's main ingredients (beans, beef, pepper, lemon, wine, egg):
- Tomatofits better
- Asparagusfits better
- Spinachfits better
- Onionthe original
Fit is the average pairing score against beans, beef, pepper, lemon, wine, egg. Candidates are from the same food group and used in at least 100 recipes.
“What each ingredient does” and “The step that matters” were written by Claude from this recipe’s own method and reviewed in samples by CompKitchen.
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