Name: Root, Heeb, and Other Savoury Pies
Ingredients: 2 pounds potatoes; 2 ounces onions; 1 ounce butter; ½ pint water; pepper to taste; coarse sea salt to taste; optional: mushrooms, hard boiled eggs, ½ ounce tapioca or sago, ketchup, celery, powdered sage, turnips, carrots, asparagus

Why it works: Potato and onion are a kitchen classic. They rank in the top 3% of all ingredient pairs, and cooks put them together in 9,023 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓

Root, Heeb, and Other Savoury Pies

Ingredients

2 pounds potatoes
2 ounces onions
1 ounce butter
½ pint water
pepper to taste
coarse sea salt to taste
optional: mushrooms, hard boiled eggs, ½ ounce tapioca or sago, ketchup, celery, powdered sage, turnips, carrots, asparagus

Directions

Prepare

Pare and cut the potatoes.
Layer small pieces of onions between the layers of potatoes.
Season with pepper and coarse sea salt.
Place small pieces of butter on top.
Pour in the water.

Bake

Cover with pastry and bake until golden.
For variation, replace onions with mushrooms or add hard boiled eggs between layers.
For added texture, wash and steep tapioca or sago in cold water before adding, or reduce to jelly and add after baking.

Recipe from a historical cookbook (Internet Archive).

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.

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.

Potato + oniontop 3% of all pairs

Smell alikemoderate

Cooked together9,023 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Butter + mushroomtop 7% of all pairs

Smell alikemoderate

Cooked together12,525 recipes

Shared aroma: trans-2-decenal (waxy, orange).
Potato + peppertop 9% of all pairs

Smell alikemoderate

Cooked together8,305 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Potato + mushroomtop 9% of all pairs

Smell alikestrong

Cooked together968 recipes

Shared aroma: 1-octen-3-one (mushroom, metallic).
Onion + mushroomtop 10% of all pairs

Smell alikemoderate

Cooked together10,626 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 pie, cooking down into soft, tender layers.
Onions: Add savory flavour that becomes sweeter as they cook between the potato layers.
Butter: Adds richness and moisture, and helps the top brown.
Water: Creates steam and moisture so the potatoes cook through in the covered pie.