Why it works: Potato and pepper are a kitchen classic. They rank in the top 9% of all ingredient pairs, and cooks put them together in 8,305 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Potato Soup
Ingredients
Directions
Prepare
Peel four or five good sized potatoes and boil them in two quarts of water.
When the potatoes are boiled soft, pour off the water, mash the potatoes finely, and return them to the water.
Finish the soup
Take a piece of butter about the size of a Qg, fry it with two tablespoonfuls of flour (and, if desired, an onion) until brown.
Then add the browned butter and flour mixture to the soup, seasoning with salt and pepper to taste.
Nutrition, whole recipe (rough)
Counts 5 of 6 ingredients. The other 1 aren't in our nutrition table and add nothing above, so the real totals are higher.
What these numbers assume: 5 portions
| Ingredient | Portion assumed | kcal |
|---|---|---|
| Flour | 1 cup (125g) all-purpose | 455 |
| Potato | 1 medium (173g) baked | 161 |
| Butter | 1 tbsp (14g) | 102 |
| Black Pepper | 1 tsp ground (2.3g) | 6 |
| Salt | 1 tsp (6g) | 0 |
| Water | not in our table | 0 |
One typical portion per ingredient; the recipe's quantities are not counted. A rough guide only, not for medical or dietary planning.
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. See the original page.
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.
-
Potato + peppertop 9% of all pairsSmell alikemoderateCooked together8,305 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Flour + buttertop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Butter + potatotop 13% of all pairsSmell alikemoderateCooked together6,456 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
-
Flour + potatotop 15% of all pairsSmell alikemoderateCooked together5,355 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Flour + peppertop 19% of all pairsSmell alikemoderateCooked together50,459 recipes
Shared aroma: isobutyraldehyde (malty, green).
Flour and butter barely smell alike, yet cooks put them together in 124,287 recipes: they work on texture and structure more than aroma.
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Potatoes
- Break down into soft, mashed bulk that thickens the soup and gives it body.
- Flour
- Cooked in butter until brown, it thickens the soup and adds a toasted, nutty flavour.
- Butter
- Fat that carries the flour's browning and adds rich flavour to the soup.
The step that matters
Frying the butter and flour until brown. Flour cooked in fat must be stirred and watched closely; too little heat leaves it raw and pasty, while overcooking scorches it and gives a bitter taste.
Swap the potato
How well each one fits the dish's main ingredients (flour, butter, pepper):
- Shallotfits better
- Chivefits about as well
- Capsicumfits about as well
- Potatothe original
Fit is the average pairing score against flour, butter, pepper. 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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