Why it works: Butter and milk are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 81,283 recipes. Both carry (z)-4-heptenal, which smells biscuit, cream. The science ↓
Escalloped Onions
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.
Prepare
Preheat the oven to 350°F (175°C).
Grease the sides and bottom of a pint tin pan.
Layer and bake
Layer fine rolled crackers in the pan, then add bits of butter, salt, and pepper.
Add a layer of sliced onions, followed by more butter, salt, and pepper, then another layer of crackers.
Repeat the layering process until all ingredients are used, finishing with a layer of crackers on top.
Pour the milk over the mixture, ensuring it rises above the layers.
Bake for 1 hour, adding more milk if necessary.
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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Butter + milktop 7% of all pairsSmell alikemoderateCooked together81,283 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
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Onion + peppertop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Onion + buttertop 15% of all pairsSmell alikemoderateCooked together42,912 recipes
Shared aroma: decanal (soap, orange peel).
-
Onion + milktop 20% of all pairsSmell alikemoderateCooked together13,418 recipes
Shared aroma: hexanal (green, grassy).
-
Butter + peppertop 21% of all pairsSmell alikemoderateCooked together85,593 recipes
Shared aroma: trans-2-nonenal (cardboard, fatty).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- White onions
- Provide the bulk of the dish and sweet, savory flavor as they soften and cook.
- Rolled crackers
- Form the crumbly layers that soak up milk and give the dish body and structure.
- Butter
- Adds fat and richness, helping flavor and browning across the layers.
- Milk
- Supplies the moisture that softens the crackers and onions as the dish bakes.
The step that matters
Pouring the milk over the layers. The milk must rise above the layers so the crackers and onions absorb enough liquid to cook through and not dry out. Adding more milk during baking, as the record advises, compensates for liquid lost to absorption and evaporation.
Swap the onion
How well each one fits the dish's main ingredients (butter, milk, pepper):
- Potatofits better
- Capsicumfits better
- Tomatofits about as well
- Onionthe original
Fit is the average pairing score against butter, milk, pepper. 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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