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, Stanislaus Style
Ingredients
Directions
The book says “a moderate oven”. The 350°F (175°C) in the steps is the modern equivalent, not the book's own figure.
Prepare
Butter the crusts of the French rolls.
Place the buttered rolls in a 350°F (175°C) oven until crisp.
Trim the ends of the onions. Peel the onions. Cut the onions in halves. Slice the onions finely.
Make the soup
In a saucepan, melt the butter.
Lightly fry the onions, stirring until nicely browned.
Add the hot water to the saucepan. Season with salt and pepper. Include the bread crusts in the saucepan. Cover the saucepan. Bring the soup to a boil. Transfer the saucepan to the oven for 30 minutes.
Serve
Serve.
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.
-
Onion + peppertop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Onion + buttertop 15% of all pairsSmell alikemoderateCooked together42,912 recipes
Shared aroma: decanal (soap, orange peel).
-
Butter + peppertop 21% of all pairsSmell alikemoderateCooked together85,593 recipes
Shared aroma: trans-2-nonenal (cardboard, fatty).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- White onions
- Browned onions form the sweet, deep flavour base of the soup.
- Butter
- Fat for frying the onions, adding richness and helping them brown.
- French rolls
- Crusts soak up the broth and thicken the soup as they break down.
The step that matters
Lightly fry the onions until nicely browned. Onions that are only pale or steamed taste flat. Slow, steady frying with stirring lets their sugars caramelise gradually, building the sweet, savoury depth the soup depends on, without scorching.
Swap the onion
How well each one fits the dish's main ingredients (butter, pepper):
- Capsicumfits better
- Potatofits better
- Carrotfits about as well
- Onionthe original
Fit is the average pairing score against butter, 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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