Why it works: Peas and parsley are a kitchen classic. They rank in the top 13% of all ingredient pairs, and cooks put them together in 1,885 recipes. Both carry trans-2-hexenal, which smells green, leafy. The science ↓
Split Pea Soup
Ingredients
Directions
Prepare the peas
Soak the split peas in soft water.
Cook the peas with 2 to 3 cups of water, simmering slowly for at least 1 hour.
Make the soup
Add salt and flavoring to taste.
Mash the peas fine with a potato masher.
Dissolve the cornstarch in cold water and stir it in.
Boil for 5 to 10 minutes, then remove from heat.
Add butter or hot cream and chopped parsley.
Serve
Serve with soda crackers or swieback.
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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Peas + parsleytop 13% of all pairsSmell alikemoderateCooked together1,885 recipes
Shared aroma: trans-2-hexenal (green, leafy).
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Butter + parsleytop 15% of all pairsSmell alikemoderateCooked together28,563 recipes
Shared aroma: trans-2-hexenal (green, leafy).
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Peas + buttertop 16% of all pairsSmell alikemoderateCooked together4,887 recipes
Shared aroma: trans-2-nonenal (cardboard, fatty).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Split peas
- Break down during long simmering to give the soup its body and thick texture.
- Cornstarch
- Thickens the soup when heated, giving it a smoother, more velvety consistency.
- Butter or hot cream
- Adds fat and richness, rounding out the flavor and softening the mouthfeel.
The step that matters
Boil for 5 to 10 minutes after adding cornstarch. Cornstarch only thickens fully when heated to a boil, and it needs stirring first so it does not form lumps. Removing the pot from heat too early can leave the soup thin and starchy-tasting.
Swap the peas
How well each one fits the dish's main ingredients (butter, parsley):
- Chickpeafits better
- Walnutfits better
- Almondfits better
- Peasthe original
Fit is the average pairing score against butter, 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.
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