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 ↓
Shirley Sauce
Ingredients
Directions
Chop the tomatoes, onions, and red peppers.
Combine all ingredients in a large pot.
Cook slowly for 3 hours, stirring occasionally.
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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Tomato + peppertop 7% of all pairsSmell alikemoderateCooked together17,923 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Tomato + oniontop 8% of all pairsSmell alikemoderateCooked together20,633 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Onion + peppertop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Onion + vinegartop 14% of all pairsSmell alikemoderateCooked together18,226 recipes
Shared aroma: acetic acid (sour, vinegar).
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Pepper + vinegartop 14% of all pairsSmell alikemoderateCooked together27,814 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Tomatoes
- Provide the bulk of the liquid and body that cooks down into the sauce.
- Vinegar
- Adds acidity that gives the sauce its sharp, tangy flavor.
- Sugar
- Balances the acidity of the vinegar and tomatoes with sweetness.
- Red peppers
- Add sweet, fresh pepper flavor and some bulk to the sauce.
The step that matters
Cook slowly for 3 hours, stirring occasionally. A long, gentle simmer lets the water evaporate and the tomatoes and peppers break down into a thick sauce. Stirring prevents the sugars and solids on the bottom from scorching.
Swap the onion
How well each one fits the dish's main ingredients (tomato, pepper, vinegar, sugar):
- Capsicumfits better
- Cucumberfits better
- Mustardfits better
- Onionthe original
Fit is the average pairing score against tomato, pepper, vinegar, sugar. 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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