Why it works: Celery and carrot match in chemistry and in kitchens. They rank in the top 1% of all ingredient pairs, and cooks put them together in 10,173 recipes. Both carry myristicin, which smells spice, warm. The science ↓
Hard Pea Soup
Ingredients
Directions
Prepare the peas
Soak the split peas overnight in water with a small piece of baking soda.
Discard any floating peas and strain the soaked peas.
Cook the soup
In a pot, combine the stock, peas, celery, carrot, and onions.
Season with curry powder or cayenne pepper.
Cover and boil until everything is soft, skimming off any scum.
Strain the soup into a warmed tureen, pressing the pulp through with a spoon.
Serve
Serve hot, adding crumbled toast to the tureen before dishing.
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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Celery + carrottop 1% of all pairsSmell alikestrongCooked together10,173 recipes
Shared aroma: myristicin (spice, warm).
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Celery + peppertop 5% of all pairsSmell alikestrongCooked together16,012 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
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Carrot + peppertop 6% of all pairsSmell alikestrongCooked together14,555 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Carrot + oniontop 6% of all pairsSmell alikemoderateCooked together21,601 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Celery + oniontop 7% of all pairsSmell alikemoderateCooked together18,518 recipes
Shared aroma: guaiacol (smoky, sweet).
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 boiling to thicken the stock and give the soup its body.
- Stock
- Forms the liquid base and carries most of the savoury flavour of the soup.
- Celery
- Adds aromatic, vegetal flavour that deepens as it simmers into the stock.
- Onions
- Contribute sweetness and savoury depth as they soften during cooking.
- Baking soda
- Raises the pot's alkalinity during soaking, helping the peas soften faster.
The step that matters
Cover and boil until everything is soft, skimming off any scum. Peas must cook long enough to break down fully, or the soup stays grainy. Skimming removes foam of impurities so the broth stays clear and clean-tasting.
Swap the peas
How well each one fits the dish's main ingredients (ham, celery, carrot, onion, pepper):
- Beansfits better
- Black-eyed peafits better
- Lentilsfits better
- Peasthe original
Fit is the average pairing score against ham, celery, carrot, onion, 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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