Name: French Dressing for Plain Lettuce Salad
Ingredients: ½ tablespoon oil; dash red pepper; 1 teaspoon vinegar; ½ teaspoon mustard; ¼ teaspoon salt; 2 drops Worcestershire sauce; 4 dashes black pepper; 2 drops tomato ketchup

Why it works: Sauce and ketchup match in chemistry and in kitchens. They rank in the top 1% of all ingredient pairs, and cooks put them together in 1,099 recipes. Both carry ethanol, which smells alcoholic, ethereal. The science ↓

French Dressing for Plain Lettuce Salad

Ingredients

Directions

Make the dressing

In a bowl, mix the oil, dash of red pepper, vinegar, mustard, salt, Worcestershire sauce, black pepper, and tomato ketchup.
If needed, repeat the proportions of oil and vinegar to make enough dressing.

Dress the lettuce

Optionally, rub the bowl with garlic before adding the lettuce.
Pour the dressing over the lettuce hearts.
Toss the lettuce to coat evenly.

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.

Sauce + ketchuptop 1% of all pairs

Smell alikestrong

Cooked together1,099 recipes

Shared aroma: ethanol (alcoholic, ethereal).
Pepper + tomatotop 7% of all pairs

Smell alikemoderate

Cooked together17,923 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Vinegar + mustardtop 7% of all pairs

Smell alikemoderate

Cooked together14,067 recipes

Shared aroma: isobutyraldehyde (malty, green).
Pepper + mustardtop 9% of all pairs

Smell alikemoderate

Cooked together15,430 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Mustard + tomatotop 11% of all pairs

Smell alikemoderate

Cooked together2,482 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).

Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs

What each ingredient does

Oil: Forms the body of the dressing and carries the flavours across the leaves.
Vinegar: Adds acidity that brightens the dressing and balances the oil.
Mustard: Adds sharpness and helps emulsify the oil and vinegar.

Swap the tomato

How well each one fits the dish's main ingredients (pepper, vinegar, mustard, sauce, ketchup):

Horseradishfits better
Capsicumfits better
Shallotfits better
Tomatothe original

Fit is the average pairing score against pepper, vinegar, mustard, sauce, ketchup. 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.