Why it works: Onion and tomato 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 ↓
Tomato Sauce
Ingredients
Directions
Make the roux
Heat 2 tablespoonfuls butter in a pan.
Beat butter and add 2 tablespoonfuls flour; stir until smooth, brown and thick.
Simmer and strain
Add a small piece of onion, 8 cloves, and tomatoes; cook for 10 minutes.
Add 1 quart tomatoes, cook for 2 minutes.
Season with salt and pepper, strain.
Nutrition, whole recipe (rough)
What these numbers assume: 6 portions
| Ingredient | Portion assumed | kcal |
|---|---|---|
| Flour | 1 cup (125g) all-purpose | 455 |
| Butter | 1 tbsp (14g) | 102 |
| Onion | 1 medium (110g) | 44 |
| Tomato | 1 medium (123g) | 22 |
| Clove | 1 tsp ground (2g) | 7 |
| Salt | 1 tsp (6g) | 0 |
One typical portion per ingredient; the recipe's quantities are not counted. A rough guide only, not for medical or dietary planning.
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. See the original page.
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 + tomatotop 8% of all pairsSmell alikemoderateCooked together20,633 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Clove + tomatotop 12% of all pairsSmell alikemoderateCooked together3,474 recipes
Shared aroma: ethyl caproate (fruity, apple peel).
-
Flour + buttertop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Clove + oniontop 13% of all pairsSmell alikemoderateCooked together16,901 recipes
Shared aroma: 2-nonanone (fruity, floral).
-
Onion + buttertop 15% of all pairsSmell alikemoderateCooked together42,912 recipes
Shared aroma: decanal (soap, orange peel).
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
- Fat that carries flavour and starts the roux with the flour.
- Flour
- Thickens the sauce as it cooks with the butter and browns slightly.
- Tomatoes
- Forms the main body of the sauce and provides its bright acidity.
- Onion
- Adds savoury aroma as it cooks into the sauce.
- Cloves
- Adds warm, aromatic spice notes to the sauce.
The step that matters
Stirring the flour into the hot butter. Flour added in lumps or left unstirred clumps and makes the sauce grainy. Stirring constantly until smooth lets the flour disperse evenly. Cooking it briefly with the fat also keeps it from tasting raw and lets it thicken the sauce properly.
Swap the clove
How well each one fits the dish's main ingredients (flour, onion, tomato, butter):
- Garlicfits better
- Capersfits better
- Thymefits better
- Clovethe original
Fit is the average pairing score against flour, onion, tomato, butter. 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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