Name: French Biscuits
Ingredients: 3 large eggs; equal weight of flour; equal weight of powdered sugar; ½ ounce candied lemon peel, finely chopped

Why it works: Flour and sugar are a kitchen classic. They rank in the top 15% of all ingredient pairs, and cooks put them together in 92,116 recipes. Both carry phenylacetaldehyde, which smells hawthorne, honey. The science ↓

French Biscuits

Oven, in the book's wordsA moderate oven

Ingredients

3 large eggs
equal weight of flour
equal weight of powdered sugar
½ ounce candied lemon peel, finely chopped

Directions

The book says “a moderate oven”. The 350°F (175°C) in the steps is the modern equivalent, not the book's own figure.

Prepare

Preheat the oven to 350°F (175°C).

Make the batter

Beat the egg whites with a whisk until frothy.
Stir in the candied lemon peel.
Gradually add the flour and powdered sugar.
Add the egg yolks and mix well.

Shape and bake

Shape the biscuits on fine white paper using a spoon.
Sprinkle powdered sugar over the biscuits.
Bake in the oven until done.
Use a fine knife to cut the biscuits from the paper and store in boxes.

Recipe from a historical cookbook (Internet Archive).

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 + sugartop 15% of all pairs

Smell alikemoderate

Cooked together92,116 recipes

Shared aroma: phenylacetaldehyde (hawthorne, honey).
Egg + flourtop 15% of all pairs

Smell alikelow

Cooked together106,462 recipes

Shared aroma: isobutyraldehyde (malty, green).
Flour + lemontop 17% of all pairs

Smell alikemoderate

Cooked together30,404 recipes

Shared aroma: isobutyraldehyde (malty, green).
Sugar + lemontop 18% of all pairs

Smell alikelow

Cooked together53,532 recipes

Shared aroma: 2-nonenal (fatty, green).
Egg + lemontop 19% of all pairs

Smell alikelow

Cooked together44,316 recipes

Shared aroma: (e,e)-2,4-decadienal (fatty, deep fried).

Egg and flour barely smell alike, yet cooks put them together in 106,462 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: Whipped whites provide air and lift, while yolks add richness and binding to the batter.
Flour: Provides the structure that holds the biscuits together as they bake.
Powdered sugar: Adds sweetness and a fine, delicate texture, and forms a light sugar coating on top.
Candied lemon peel: Adds bright citrus aroma and flavor, along with a slightly chewy bite.