Why it works: Spinach and pepper are a kitchen classic. They rank in the top 6% of all ingredient pairs, and cooks put them together in 3,400 recipes. Both carry nonanal, which smells fat, citrus. The science ↓
Spinach Soup
Ingredients
Directions
Prepare the spinach
Wash the spinach and remove the stalks.
Place the spinach in a saucepan with just enough water to cover the bottom to prevent burning.
Cook until tender, then drain and rub through a fine sieve.
Make the soup
Melt the butter or fat in a stewpan, then sprinkle in the flour and cook for a few minutes.
Gradually add the spinach puree and stock, stirring continuously.
Bring to a boil, then add the milk and simmer for a few minutes.
Season with pepper and salt to taste, then serve.
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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Spinach + peppertop 6% of all pairsSmell alikemoderateCooked together3,400 recipes
Shared aroma: nonanal (fat, citrus).
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Milk + buttertop 7% of all pairsSmell alikemoderateCooked together81,283 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
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Spinach + flourtop 10% of all pairsSmell alikemoderateCooked together1,564 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Butter + flourtop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Milk + flourtop 14% of all pairsSmell alikelowCooked together78,219 recipes
Shared aroma: isobutyraldehyde (malty, green).
Butter and flour 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
- Spinach
- Forms the body and green colour of the soup once pureed.
- Flour
- Cooked in fat to make a roux that thickens the soup.
- Butter or good fat
- Carries flavour and forms the base of the roux with the flour.
- White second stock
- Adds liquid and savoury flavour to thin the spinach puree.
- Milk
- Adds creaminess and mellows the soup's flavour at the end.
The step that matters
Cooking the flour in the fat. Cooking the flour in the melted fat for a few minutes cooks out its raw starchy taste. Stirring in the stock and puree gradually keeps the roux smooth instead of lumpy.
Swap the spinach
How well each one fits the dish's main ingredients (milk, butter, flour, pepper):
- Potatofits better
- Capsicumfits better
- Chivefits about as well
- Spinachthe original
Fit is the average pairing score against milk, butter, flour, 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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