Why it works: Butter and bread are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 27,232 recipes. Both carry delta-decalactone, which smells sweet, creamy. The science ↓
Potatoes Au Gratin
Ingredients
Directions
The book says “a quick oven”. The 400°F (200°C) in the steps is the modern equivalent, not the book's own figure.
Make the sauce
Melt the butter or butter substitute in a frying pan.
Add the flour and mix until smooth.
Gradually add the milk, stirring continually until it boils.
Remove from heat and stir in the cheese, salt, and pepper.
Assemble and bake
In a baking dish, layer some of the sauce, followed by sliced cold potatoes, and repeat, finishing with sauce on top.
Sprinkle bread crumbs over the top.
Bake in a 400°F (200°C) oven for 10 minutes to brown.
Serve in the baking 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.
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 + breadtop 7% of all pairsSmell alikemoderateCooked together27,232 recipes
Shared aroma: delta-decalactone (sweet, creamy).
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Milk + buttertop 7% of all pairsSmell alikemoderateCooked together81,283 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
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Cheese + breadtop 7% of all pairsSmell alikemoderateCooked together2,130 recipes
Shared aroma: delta-decalactone (sweet, creamy).
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Cheese + buttertop 8% of all pairsSmell alikemoderateCooked together7,962 recipes
Shared aroma: delta-dodecalactone (sweet, creamy).
-
Potato + peppertop 9% of all pairsSmell alikemoderateCooked together8,305 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
- Potatoes
- Form the bulk of the dish, holding the layers together and giving a soft, starchy body.
- Flour
- Thickens the butter and milk into a smooth sauce that coats the potatoes.
- Milk
- Forms the liquid base of the sauce, giving it creaminess once thickened.
- Cheese
- Adds savory flavor and richness to the sauce and helps it brown on top.
- Butter
- Provides fat for the roux, adding richness and a rounded flavor to the sauce.
The step that matters
Thickening the milk into sauce. Stirring continually while the milk heats keeps the flour evenly dispersed, preventing lumps. Bringing it to a boil activates the starch so the sauce thickens properly.
Swap the potato
How well each one fits the dish's main ingredients (flour, milk, cheese, butter, pepper, bread):
- Potatothe original
- Capsicumfits about as well
- Tomatofits about as well
- Asparagusfits about as well
Fit is the average pairing score against flour, milk, cheese, butter, pepper, 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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