Why it works: Onion and bread are a kitchen classic. They rank in the top 15% of all ingredient pairs, and cooks put them together in 8,676 recipes. Both carry 2,4-decadienal, which smells seaweed. The science ↓
Onion Sandwiches
Ingredients
Directions
Peel and finely chop the onion.
Mix the chopped onion with mayonnaise.
Spread the mixture on the thin slices of bread.
Cut the sandwiches into any desired shape.
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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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
- Onion
- Provides the sharp, pungent flavor that defines the sandwich.
- Mayonnaise
- Adds fat and moisture, binding the chopped onion and softening the bread.
- Bread
- Forms the thin structure that holds the onion spread.
The step that matters
Finely chopping the onion. Fine pieces release their flavor evenly and spread smoothly, while coarse chunks stay sharp and can slide off thin bread. Raw onion's harshness is mellowed by the fat in the mayonnaise.
“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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