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 ↓
Potatoes Au Gratin
Ingredients
Directions
The book says “a moderate oven”. The 350°F (175°C) in the steps is the modern equivalent, not the book's own figure.
Make the sauce
In a saucepan, heat the butter over medium heat.
Add the flour, salt, and pepper, stirring until hot.
Gradually add the milk, cooking until the sauce is smooth.
Assemble and bake
Fold in the sliced potatoes and heat through.
Transfer to buttered individual dishes or a baking dish.
Gently mix in the chopped cheese.
Bake for about 10 minutes at 350°F (175°C).
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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Butter + cheesetop 8% of all pairsSmell alikemoderateCooked together7,962 recipes
Shared aroma: delta-dodecalactone (sweet, creamy).
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Potato + peppertop 9% of all pairsSmell alikemoderateCooked together8,305 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Potato + milktop 9% of all pairsSmell alikemoderateCooked together3,611 recipes
Shared aroma: (e,z)-2,6-nonadienal (cucumber, melon).
-
Milk + cheesetop 10% of all pairsSmell alikemoderateCooked together4,426 recipes
Shared aroma: delta-dodecalactone (sweet, creamy).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Potatoes
- Form the body of the dish, absorbing the sauce and becoming tender as they bake.
- Butter
- Enriches the sauce and adds fat for a rich flavor and smooth texture.
- Flour
- Thickens the milk into a smooth sauce that holds the potatoes together.
- Milk
- Forms the liquid base of the sauce, giving it creaminess.
- Cheese
- Melts into the sauce to add savory flavor and richness.
The step that matters
Gradually add the milk, cooking until the sauce is smooth.. Adding milk slowly while stirring lets the starch in the flour disperse evenly, preventing lumps and giving a smooth, properly thickened sauce.
Swap the potato
How well each one fits the dish's main ingredients (butter, flour, pepper, milk, cheese):
- Potatothe original
- Capsicumfits about as well
- Asparagusfits less well
- Chivefits less well
Fit is the average pairing score against butter, flour, pepper, milk, cheese. 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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