Name: Scalloped Potatoes
Ingredients: one pint of milk; one-half pound of cold boiled potatoes; two ounces of onions; a cupful of milk; a piece of butter size of an egg; six boiled potatoes in small pieces; three spoons of flour; seven potatoes the moment they are done; two waters; butter the size of an egg; salt; pepper; parsley

Why it works: Pepper and parsley match in chemistry and in kitchens. They rank in the top 2% of all ingredient pairs, and cooks put them together in 34,122 recipes. Both carry 4'-methylacetophenone, which smells bitter almond. The science ↓

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.

Pepper + parsleytop 2% of all pairs

Smell alikestrong

Cooked together34,122 recipes

Shared aroma: 4'-methylacetophenone (bitter almond).
Potato + oniontop 3% of all pairs

Smell alikemoderate

Cooked together9,023 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Potato + parsleytop 5% of all pairs

Smell alikemoderate

Cooked together2,855 recipes

Shared aroma: 4'-methylacetophenone (bitter almond).
Milk + buttertop 7% of all pairs

Smell alikemoderate

Cooked together81,283 recipes

Shared aroma: (z)-4-heptenal (biscuit, cream).
Onion + parsleytop 9% of all pairs

Smell alikemoderate

Cooked together25,843 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

Potatoes: Form the bulk of the dish, giving body and a soft, tender texture once baked.
Flour: Thickens the milk into a smooth dressing that holds the layers together.
Milk: Forms the sauce base that moistens the potatoes and sets into a creamy custard as it bakes.
Butter: Adds richness and fat, carrying flavor and helping the top brown.

The step that matters

Boil the dressing until it thickens. Flour must be cooked in the hot milk until it thickens; if the dressing is underheated, it stays thin and floury and will not bind the potato layers.

Swap the onion

How well each one fits the dish's main ingredients (milk, potato, butter, egg, flour, pepper, parsley):

Chivefits better
Shallotfits better
Asparagusfits better
Onionthe original

Fit is the average pairing score against milk, potato, butter, egg, flour, pepper, parsley. 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.

Ingredient	Portion assumed	kcal
Flour	1 cup (125g) all-purpose	455
Potato	1 medium (173g) baked	161
Milk	1 cup (244ml) whole	149
Butter	1 tbsp (14g)	102
Egg	1 large egg (50g)	78
Onion	1 medium (110g)	44
Black Pepper	1 tsp ground (2.3g)	6
Parsley	1 tbsp chopped fresh (3.8g)	1
Salt	1 tsp (6g)	0
Water	not in our table	0

Scalloped Potatoes