Why it works: Onion and mustard match in chemistry and in kitchens. They rank in the top 6% of all ingredient pairs, and cooks put them together in 9,259 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Quick Tomato Rarebit
Ingredients
Directions
Make the sauce
Cook onion and green pepper in fat until tender.
Heat soup in the top of a double boiler.
Add cheese to soup and cook over boiling water, stirring constantly, until cheese is melted and mixture is smooth.
Stir in mustard, worcestershire sauce, onion, and green pepper.
Serve
Serve over toast pieces.
Garnish with a sprig of parsley, if desired.
Nutrition, whole recipe (rough)
Counts 8 of 9 ingredients. The other 1 aren't in our nutrition table and add nothing above, so the real totals are higher.
What these numbers assume: 8 portions
| Ingredient | Portion assumed | kcal |
|---|---|---|
| Cheese | 1 oz (28g) cheddar | 113 |
| Cheddar Cheese | 1 oz (28g) | 113 |
| Butter | 1 tbsp (14g) | 102 |
| Onion | 1 medium (110g) | 44 |
| Bell Pepper | 1 medium (119g) | 31 |
| Tomato | 1 medium (123g) | 22 |
| Soy Sauce | 1 tbsp (15ml) | 9 |
| Mustard | 1 tsp (5g) yellow | 3 |
| Soup | not in our table | 0 |
One typical portion per ingredient; the recipe's quantities are not counted. A rough guide only, not for medical or dietary planning.
Steps grouped into stages for easier reading; the method is the source's own.
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 + mustardtop 6% of all pairsSmell alikestrongCooked together9,259 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Pepper + tomatotop 7% of all pairsSmell alikemoderateCooked together17,923 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Onion + tomatotop 8% of all pairsSmell alikemoderateCooked together20,633 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Butter + cheesetop 8% of all pairsSmell alikemoderateCooked together7,962 recipes
Shared aroma: delta-dodecalactone (sweet, creamy).
-
Pepper + mustardtop 9% of all pairsSmell alikemoderateCooked together15,430 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
- Pasteurized process cheese
- Melts into the soup to give the rarebit its smooth, rich, sauce-like body.
- Tomato soup, condensed
- Forms the liquid base of the sauce and adds tomato flavor and moisture.
- Sharp cheddar
- Adds sharp, savory cheese flavor to the sauce.
- Onion
- Adds savory sweetness and aroma once softened in fat.
- Green pepper
- Adds fresh, slightly bitter vegetable flavor and texture once softened in fat.
The step that matters
Melting the cheese over boiling water. Cheese turns grainy or oily if it overheats or boils hard, so keeping the water at a simmer under the double boiler and stirring constantly helps the cheese melt into a smooth sauce.
Swap the tomato
How well each one fits the dish's main ingredients (onion, pepper, butter, cheese, mustard, sauce):
- Horseradishfits better
- Chivefits better
- Capsicumfits better
- Tomatothe original
Fit is the average pairing score against onion, pepper, butter, cheese, mustard, sauce. 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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