Why it works: Lemon and pepper match in chemistry and in kitchens. They rank in the top 3% of all ingredient pairs, and cooks put them together in 27,047 recipes. Both carry trans-2-nonenal, which smells cardboard, fatty. The science ↓
Tomato Rarebit
Ingredients
Directions
Make the sauce
Melt the butter in a saucepan.
Add the chopped tomato and cook until soft.
Pass the mixture through a sieve back into the saucepan.
Finish and serve
Return to the heat and add lemon juice, catsup, salt, pepper, and cheese.
Cook until the cheese is melted.
Serve on hot, buttered toast.
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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Lemon + peppertop 3% of all pairsSmell alikestrongCooked together27,047 recipes
Shared aroma: trans-2-nonenal (cardboard, fatty).
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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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Butter + cheesetop 8% of all pairsSmell alikemoderateCooked together7,962 recipes
Shared aroma: delta-dodecalactone (sweet, creamy).
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Tomato + lemontop 11% of all pairsSmell alikemoderateCooked together4,592 recipes
Shared aroma: 3-hexenal (apple, fruity).
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Tomato + cheesetop 13% of all pairsSmell alikemoderateCooked together2,896 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
- Butter
- Adds richness and helps the tomato mixture feel smooth and silky.
- Tomato
- Supplies the main body and fresh, acidic flavor of the topping.
- Grated cheese
- Melts into the sauce to add savoriness and a creamy, binding texture.
- Catsup
- Adds sweetness and tang that deepen the tomato flavor.
The step that matters
Cook the cheese until just melted. Cheese turns stringy and oily if overheated, so it should be stirred in over gentle heat until it melts smoothly into the sauce.
Swap the lemon
How well each one fits the dish's main ingredients (butter, tomato, pepper, cheese):
- Plumfits better
- Mangofits better
- Avocadofits about as well
- Lemonthe original
Fit is the average pairing score against butter, tomato, pepper, 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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