Why it works: Onion and pepper are a kitchen classic. They rank in the top 11% of all ingredient pairs, and cooks put them together in 68,474 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Onion Soup
4 personsIngredients
Directions
Prepare and cook the onions
Chop the onions.
Put them in the butter.
Stir them occasionally, but do not let them brown.
When tender, put the stock to them and season.
Finish the soup
Strain the soup.
Add the boiling cream.
Nutrition, whole recipe (rough)
What these numbers assume: 4 portions
| Ingredient | Portion assumed | kcal |
|---|---|---|
| Cream | 1 tbsp (15ml) heavy | 51 |
| Onion | 1 medium (110g) | 44 |
| Black Pepper | 1 tsp ground (2.3g) | 6 |
| Salt | 1 tsp (6g) | 0 |
One typical portion per ingredient; the recipe's quantities are not counted. A rough guide only, not for medical or dietary planning.
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. See the original page.
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.
-
Onion + peppertop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Cream + oniontop 18% of all pairsSmell alikelowCooked together10,827 recipes
Shared aroma: 2-nonanone (fruity, floral).
-
Cream + peppertop 23% of all pairsSmell alikelowCooked together21,449 recipes
Shared aroma: acetic acid (sour, vinegar).
Cream and onion barely smell alike, yet cooks put them together in 10,827 recipes: they work on texture and structure more than aroma.
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Onions
- Soften slowly to build a sweet, mellow base for the soup.
- Stock
- Forms the liquid base that carries the soup's main flavor.
- Cream
- Adds richness and a smooth, silky texture at the end.
The step that matters
Stir the onions without letting them brown. Gentle, slow softening draws out the onions' natural sweetness and keeps the soup pale and mild. Browning adds a bitter, toasted flavor that changes the character of the soup.
Swap the onion
How well each one fits the dish's main ingredients (cream, pepper):
- Spinachfits better
- Capsicumfits better
- Potatofits better
- Onionthe original
Fit is the average pairing score against cream, pepper. 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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