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 gives no oven temperature. The 400°F (200°C) in the steps was added when the recipe was transcribed, as a starting point.
Prepare
Peel the potatoes and cook them until nearly done, then slice them.
Layer and bake
In a baking dish, layer the sliced potatoes and grated cheese, adding butter, salt, and pepper between layers.
Continue layering until the dish is full, ensuring the top layer is cheese.
Pour milk over the layers and bake at 400°F (200°C) until brown.
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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Cheese + buttertop 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).
-
Cheese + milktop 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 bulk of the dish and set into tender layers as they bake.
- Grated cheese
- Melts into the layers and browns on top, adding richness and savoury flavour.
- Butter
- Adds fat that enriches the layers and helps the top brown.
- Milk
- Provides moisture that cooks into a sauce around the potatoes.
The step that matters
Parboil the potatoes until nearly done. Starch in potatoes softens as it cooks. Stopping at nearly done lets the slices finish tender in the oven without turning mushy or staying firm in the middle.
Swap the potato
How well each one fits the dish's main ingredients (cheese, butter, pepper, milk):
- Potatothe original
- Capsicumfits about as well
- Tomatofits less well
- Asparagusfits less well
Fit is the average pairing score against cheese, butter, pepper, milk. 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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