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 ↓
Split Pea Soup
Ingredients
Directions
Prepare the peas
Wash the split peas well and soak them in cold water for 24 hours.
In a pot, boil the soaked peas in fresh water until soft, adding more water as needed.
Once soft, mash the peas through a strainer.
Make the creamed base
Melt the butter in a separate pan.
Stir in the flour and seasonings.
Gradually add the milk to the butter mixture until it reaches a thick, creamy consistency.
Combine and serve
Combine the strained peas with the creamed milk and cook together for 10 minutes.
Serve with fried bread cubes.
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.
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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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Flour + buttertop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Flour + milktop 14% of all pairsSmell alikelowCooked together78,219 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Peas + peppertop 15% of all pairsSmell alikemoderateCooked together5,331 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Peas + milktop 16% of all pairsSmell alikemoderateCooked together1,309 recipes
Shared aroma: hexanal (green, grassy).
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
- Dried split peas
- Provide the main body and starch that thicken the soup as they soften and break down.
- Butter
- Adds richness and carries flavour, forming the base for the thickened milk mixture.
- Flour
- Thickens the butter and milk mixture so the soup becomes creamy rather than watery.
- Milk
- Adds creaminess and body, thickening the soup further when combined with the flour roux.
The step that matters
Gradually adding the milk to the butter and flour. Adding milk slowly while stirring keeps the flour smooth and lump-free, so the mixture thickens evenly instead of clumping.
Swap the peas
How well each one fits the dish's main ingredients (flour, butter, pepper, milk):
- Almondfits better
- Chestnutfits better
- Milletfits better
- Peasthe original
Fit is the average pairing score against flour, 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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