Why it works: Beef and onion 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 ↓
Onion Soup
Ingredients
Directions
Prepare
Slice the round steak into ½ inch slices and then cut them into ½ inch squares.
In a saucepan, heat the beef drippings and butter over medium heat.
Slice the onions thinly and fry them until slightly browned.
Make the soup
Add the meat to the onions and cook slowly for about 15 minutes.
Season with salt to taste, then add 2 quarts of water.
Let the mixture simmer on low heat for 4 hours.
Serve
Ladle the soup into bowls and top each with an inch of melted American cheese.
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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Beef + oniontop 7% of all pairsSmell alikemoderateCooked together17,092 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Butter + cheesetop 8% of all pairsSmell alikemoderateCooked together7,962 recipes
Shared aroma: delta-dodecalactone (sweet, creamy).
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Beef + cheesetop 15% of all pairsSmell alikemoderateCooked together1,193 recipes
Shared aroma: 12-methyltridecanal (tallowy, beefy).
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Butter + oniontop 15% of all pairsSmell alikemoderateCooked together42,912 recipes
Shared aroma: decanal (soap, orange peel).
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Onion + cheesetop 16% of all pairsSmell alikemoderateCooked together4,849 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
- Round steak
- Provides the meat and savory beef flavor that the soup is built around.
- Onions
- Caramelized sweetness and body that give the soup its characteristic flavor.
- Beef drippings
- Adds rich, savory fat that carries flavor and helps brown the onions.
- Butter
- Adds fat and a rounded, buttery flavor to the initial frying.
- American cheese
- Melts over the hot soup to add richness and a creamy, salty topping.
The step that matters
Fry the onions until slightly browned. Browning onions develops sweet, deeper flavors through caramelization, which form the base of the soup. Pale onions yield a flatter, less savory broth.
Swap the onion
How well each one fits the dish's main ingredients (beef, butter, cheese):
- Potatofits about as well
- Onionthe original
- Tomatofits about as well
- Chivefits less well
Fit is the average pairing score against beef, butter, 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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