Why it works: Tomato and onion are a kitchen classic. They rank in the top 8% of all ingredient pairs, and cooks put them together in 20,633 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Macaroni with Tomato Sauce
Ingredients
Directions
The book gives no oven temperature. The 350°F (175°C) in the steps was added when the recipe was transcribed, as a starting point.
Make the sauce
Melt butter in a saucepan over low heat, then mix with flour.
Remove from heat, slowly add tomato juice, stirring constantly.
Add salt, sugar, and onion slice, then boil until sauce thickens.
Remove onion from sauce.
Assemble and bake
In a buttered baking dish, layer cooked macaroni and tomato sauce alternately.
Top with buttered crumbs and bake at 350°F (175°C) until heated through and crumbs are browned.
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.
Photo for illustrative purposes only · Contact us to use it
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 + oniontop 8% of all pairsSmell alikemoderateCooked together20,633 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Flour + buttertop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Flour + sugartop 15% of all pairsSmell alikemoderateCooked together92,116 recipes
Shared aroma: phenylacetaldehyde (hawthorne, honey).
-
Butter + oniontop 15% of all pairsSmell alikemoderateCooked together42,912 recipes
Shared aroma: decanal (soap, orange peel).
-
Sugar + buttertop 17% of all pairsSmell alikemoderateCooked together98,233 recipes
Shared aroma: guaiacol (smoky, sweet).
Flour and butter barely smell alike, yet cooks put them together in 124,287 recipes: they work on texture and structure more than aroma.
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Butter
- Enriches the sauce and, with flour, forms a roux that thickens it.
- Flour
- Thickens the sauce when cooked with butter into a roux.
- Tomato juice
- Forms the liquid base of the sauce and provides its acidity and flavour.
- Macaroni
- Provides the starchy body of the dish, layered with the sauce.
The step that matters
Add the tomato juice slowly while stirring. Adding liquid gradually to a hot butter and flour roux while stirring keeps it smooth. Dumping it in all at once can form lumps that are hard to remove.
Swap the tomato
How well each one fits the dish's main ingredients (flour, sugar, butter, onion):
- Leekfits better
- Chivefits better
- Okrafits better
- Tomatothe original
Fit is the average pairing score against flour, sugar, butter, onion. 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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