Why it works: Onion and beef are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 17,092 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Traditional French Onion Soup
Ingredients
Directions
Make the soup
Melt butter in large skillet.
Add onions; cook over moderately low heat 30 minutes, stirring frequently.
In large saucepan combine onions, beef broth, water, salt and pepper.
Bring to a boil.
Reduce heat; cover and simmer 1 hour.
Serve
Toast bread.
Place toast in one large or in individual bowls.
Add soup; sprinkle toast with cheese.
Serve with additional cheese, if desired.
Nutrition, whole recipe (rough)
Counts 7 of 9 ingredients. The other 2 aren't in our nutrition table and add nothing above, so the real totals are higher.
What these numbers assume: 7 portions
| Ingredient | Portion assumed | kcal |
|---|---|---|
| Flour | 1 cup (125g) all-purpose | 455 |
| Beef | 100g cooked | 250 |
| Parmesan Cheese | 1 oz (28g) | 110 |
| Butter | 1 tbsp (14g) | 102 |
| Onion | 1 medium (110g) | 44 |
| Black Pepper | 1 tsp ground (2.3g) | 6 |
| Salt | 1 tsp (6g) | 0 |
| Soup | not in our table | 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.
Steps grouped into stages for easier reading; the method is the source's own.
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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Onion + beeftop 7% of all pairsSmell alikemoderateCooked together17,092 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Butter + breadtop 7% of all pairsSmell alikemoderateCooked together27,232 recipes
Shared aroma: delta-decalactone (sweet, creamy).
-
Butter + parmesan cheesetop 9% of all pairsSmell alikemoderateCooked together4,163 recipes
Shared aroma: guaiacol (smoky, sweet).
-
Beef + peppertop 10% of all pairsSmell alikemoderateCooked together18,971 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
- Slow cooking softens and sweetens the onions, building the soup's main flavor.
- Butter or margarine
- Fat carries flavor and helps the onions brown gently in the skillet.
- Beef broth
- Forms the liquid base of the soup and supplies savory, meaty flavor.
- French bread
- Soaks up the broth and gives the soup body when served on top.
- Parmesan cheese
- Melts over the toast and adds salty, savory flavor and browning.
The step that matters
Cook the onions over moderately low heat. Slow, gentle cooking lets onion sugars caramelize gradually and turn sweet and brown. Higher heat can scorch them before they soften, leaving a bitter taste.
Swap the onion
How well each one fits the dish's main ingredients (butter, beef, pepper, bread, parmesan cheese):
- Tomatofits better
- Potatofits about as well
- Asparagusfits about as well
- Onionthe original
Fit is the average pairing score against butter, beef, pepper, bread, parmesan cheese. 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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