Name: Stuffed Peppers
Ingredients: ½ cup rice; 2 cups brown stock; ¼ cup melted butter; a few drops onion juice; 1 tablespoon tomato ketchup; salt to taste; pepper to taste; buttered cracker crumbs

Why it works: Rice and tomato match in chemistry and in kitchens. They rank in the top 6% of all ingredient pairs, and cooks put them together in 3,065 recipes. Both carry trans-2-nonenal, which smells cardboard, fatty. The science ↓

Stuffed Peppers

Ingredients

Directions

Cook the rice in brown stock until tender.
Stir in melted butter, onion juice, tomato ketchup, salt, and pepper.
Remove seeds from the peppers and fill them with the rice mixture.
Top with buttered cracker crumbs.
Bake until the crumbs are brown.

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.

Rice + tomatotop 6% of all pairs

Smell alikestrong

Cooked together3,065 recipes

Shared aroma: trans-2-nonenal (cardboard, fatty).
Tomato + peppertop 7% of all pairs

Smell alikemoderate

Cooked together17,923 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Onion + tomatotop 8% of all pairs

Smell alikemoderate

Cooked together20,633 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Rice + oniontop 9% of all pairs

Smell alikemoderate

Cooked together10,433 recipes

Shared aroma: 2,4-decadienal (seaweed).
Onion + peppertop 11% of all pairs

Smell alikemoderate

Cooked together68,474 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

Swap the onion

How well each one fits the dish's main ingredients (rice, butter, tomato, ketchup, pepper):

Capsicumfits better
Carrotfits better
Potatofits about as well
Onionthe original

Fit is the average pairing score against rice, butter, tomato, ketchup, pepper. Candidates are from the same food group and used in at least 100 recipes.