Why it works: Tomato and pepper are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 17,923 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Portuguese Soup
Ingredients
Directions
Make the soup
Slice the onions and fry them until brown.
Add the tomatoes, skinned and sliced, the water, herbs, pepper, and salt, and let the whole boil gently for 1 hour.
Assemble and serve
Cut up the bread into dice, and put it into the tureen.
Pour the soup over it, cover, and let it stand for 10 minutes to allow the bread to soak.
Sprinkle the cheese over before serving.
Nutrition, whole recipe (rough)
Counts 4 of 5 ingredients. The other 1 aren't in our nutrition table and add nothing above, so the real totals are higher.
What these numbers assume: 4 portions
| Ingredient | Portion assumed | kcal |
|---|---|---|
| Onion | 1 medium (110g) | 44 |
| Tomato | 1 medium (123g) | 22 |
| Black Pepper | 1 tsp ground (2.3g) | 6 |
| Salt | 1 tsp (6g) | 0 |
| Water | not in our table | 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.
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Tomato + peppertop 7% of all pairsSmell alikemoderateCooked together17,923 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Onion + tomatotop 8% of all pairsSmell alikemoderateCooked together20,633 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Onion + peppertop 11% of all pairsSmell alikemoderateCooked together68,474 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
- Onions
- Frying until brown builds deep, savoury flavour that forms the base of the soup.
- Tomatoes
- Add acidity and body, and their juices help make up the liquid of the soup.
- Bread (in the method)
- Soaks up the hot soup, becoming soft and giving the dish its substance.
The step that matters
Frying the onions until brown. Onions turn brown through the Maillard reaction and caramelisation, which create the savoury depth the soup depends on. Stopping too early leaves a pale, flat flavour, while over-browning makes the soup bitter.
Swap the onion
How well each one fits the dish's main ingredients (tomato, pepper):
- Capsicumfits better
- Eggplantfits better
- Carrotfits better
- Onionthe original
Fit is the average pairing score against tomato, 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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