Why it works: Pepper and lemon match in chemistry and in kitchens. They rank in the top 3% of all ingredient pairs, and cooks put them together in 27,047 recipes. Both carry trans-2-nonenal, which smells cardboard, fatty. The science ↓
A Gravy, Without Meat
Ingredients
Directions
Combine small beer, water, pepper, salt, grated lemon peel, bruised cloves, and walnut pickle or mushroom ketchup in a bowl.
Melt butter in a pan and fry the sliced onion until brown.
Add the beer mixture to the pan with the onion and simmer covered for 20 minutes.
Strain the gravy, let it cool, then remove the fat.
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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Pepper + lemontop 3% of all pairsSmell alikestrongCooked together27,047 recipes
Shared aroma: trans-2-nonenal (cardboard, fatty).
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Pepper + clovetop 5% of all pairsSmell alikestrongCooked together17,451 recipes
Shared aroma: ethyl octanoate (fruity, wine).
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Clove + walnuttop 9% of all pairsSmell alikestrongCooked together1,592 recipes
Shared aroma: eucalyptol (eucalyptus, herbal).
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Lemon + clovetop 10% of all pairsSmell alikestrongCooked together8,150 recipes
Shared aroma: eucalyptol (eucalyptus, herbal).
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Lemon + walnuttop 10% of all pairsSmell alikestrongCooked together2,149 recipes
Shared aroma: 2-nonenal (fatty, green).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Onion
- Browning in butter builds a deep, savoury flavour base for the gravy.
- Butter
- Fat that carries flavour and helps the onion brown.
- Walnut pickle or mushroom ketchup
- Adds concentrated savoury depth, standing in for the meat flavour.
The step that matters
Frying the onion until brown. Browning the onion in butter develops sweet, roasted flavours through the Maillard reaction. Pale onions give a flat, weak gravy, so cook until the slices are properly browned before adding liquid.
Swap the onion
How well each one fits the dish's main ingredients (beer, pepper, lemon, clove, walnut, butter):
- Capsicumfits better
- Shallotfits better
- Lettucefits better
- Onionthe original
Fit is the average pairing score against beer, pepper, lemon, clove, walnut, butter. 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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