Why it works: Flour and butter are a kitchen classic. They rank in the top 12% of all ingredient pairs, and cooks put them together in 124,287 recipes. Both carry isobutyraldehyde, which smells malty, green. The science ↓
Lemon Pie
Ingredients
Directions
Make the filling
Beat the yolks of the eggs until light.
Mix the sugar and flour together.
Slowly add the boiling water to the mixture.
Cook for 20 minutes, stirring frequently.
Add the mixture to the beaten egg, then add butter and lemon.
Cook until the egg thickens.
Assemble and bake
Once cool, pour the mixture into a baked pie crust.
Cover with meringue and bake until golden brown.
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.
-
Flour + buttertop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Flour + sugartop 15% of all pairsSmell alikemoderateCooked together92,116 recipes
Shared aroma: phenylacetaldehyde (hawthorne, honey).
-
Flour + eggtop 15% of all pairsSmell alikelowCooked together106,462 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Lemon + buttertop 16% of all pairsSmell alikemoderateCooked together41,227 recipes
Shared aroma: 3-hexenal (apple, fruity).
-
Flour + lemontop 17% of all pairsSmell alikemoderateCooked together30,404 recipes
Shared aroma: isobutyraldehyde (malty, green).
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
- Eggs
- Yolks thicken the lemon filling as they cook and set it into a custard.
- Flour
- Starch that thickens the filling and keeps it from running when cut.
- Sugar
- Sweetens the filling and balances the sharpness of the lemon.
- Butter
- Adds richness and a smooth, glossy texture to the filling.
- Lemon
- Provides acidity and aroma that cut through the sweetness.
The step that matters
Cook until the egg thickens. Egg yolks must be cooked gently while stirring; if overheated they curdle, and if underheated the filling stays runny and will not set once cooled.
Swap the lemon
How well each one fits the dish's main ingredients (flour, sugar, butter, egg):
- Raisinfits better
- Vanillafits better
- Figfits about as well
- Lemonthe original
Fit is the average pairing score against flour, sugar, butter, egg. 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.
You might also like
The free Flavor Lab newsletter: one surprising pairing a week and the molecular reason it works, in 60 seconds. No spam, unsubscribe anytime.
Prefer an account? Create a free account to save pairings and unlock the full chemistry.
Lemon Cake228 recipes
Lemon Ice147 recipes
Lemon Sherbet103 recipes
Lemon Custard64 recipes