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 ↓
Mock Beef Steaks
Ingredients
Directions
Prepare the bread
Cut the brown bread into medium-thick slices and remove the crust from the slices.
Dip the bread slices in tomato sauce or mushroom ketchup to flavor them.
Sprinkle a little salt over the bread.
Fry the bread in nutter or Albene until golden brown.
Prepare the tomatoes and onions
Dip the tomatoes in boiling water, then peel the tomatoes.
Slice the tomatoes.
Fry the tomato slices.
Slice the onions.
Fry the onions.
Assemble
Place the fried tomato slices on the fried bread.
Arrange the fried onions around the dish.
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 + oniontop 8% of all pairsSmell alikemoderateCooked together20,633 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Tomato + breadtop 10% of all pairsSmell alikemoderateCooked together1,013 recipes
Shared aroma: 2-nonenal (fatty, green).
-
Onion + breadtop 15% of all pairsSmell alikemoderateCooked together8,676 recipes
Shared aroma: 2,4-decadienal (seaweed).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Tomatoes
- Provide moisture, acidity and a sweet, savory flavor that sits on the bread.
- Onions
- Add sweetness and aroma as they soften and brown in the frying fat.
- Brown bread
- Forms the crisp, golden base that holds the toppings.
The step that matters
Fry the bread in nutter or Albene until golden brown.. Frying in fat browns the bread's surface through the Maillard reaction, creating flavor and a crisp texture. Stop at golden brown, since further frying dries and bitters the surface.
Swap the onion
How well each one fits the dish's main ingredients (tomato, bread):
- Capsicumfits better
- Eggplantfits better
- Cucumberfits better
- Onionthe original
Fit is the average pairing score against tomato, bread. 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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