Name: Gravy or Sauce for a Goose
Ingredients: 2 ounces mild onion, chopped; 2 tablespoons butter; 1 teaspoon flour; ⅓ cup good brown gravy; 1 teaspoon made mustard; ⅓ cup port wine; cayenne pepper, to taste; coarse sea salt, to taste

Why it works: Onion and mustard match in chemistry and in kitchens. They rank in the top 6% of all ingredient pairs, and cooks put them together in 9,259 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓

Gravy or Sauce for a Goose

Ingredients

Directions

Melt the butter and add the chopped onion.
Cook until the onion begins to brown.
Stir in the flour and cook for 5 to 6 minutes.
Gradually pour in the brown gravy and let it simmer for 15 minutes.
Strain the sauce and bring it back to a boil.
Mix the mustard with the port wine and add to the sauce.
Season with cayenne pepper and salt if needed.
Serve very hot.

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.

Onion + mustardtop 6% of all pairs

Smell alikestrong

Cooked together9,259 recipes

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

Smell alikemoderate

Cooked together15,430 recipes

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

Smell alikemoderate

Cooked together68,474 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Butter + flourtop 12% of all pairs

Smell alikelow

Cooked together124,287 recipes

Shared aroma: isobutyraldehyde (malty, green).
Flour + mustardtop 13% of all pairs

Smell alikemoderate

Cooked together5,066 recipes

Shared aroma: isobutyraldehyde (malty, green).

Butter and flour 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

Flour: Thickens the gravy as it cooks with the butter and onion.
Butter: Carries the onion flavour and adds richness to the sauce.
Port wine: Adds sweetness and depth to the sauce.
Made mustard: Adds sharpness that balances the richness of the gravy.

The step that matters

Stir in the flour and cook for 5 to 6 minutes. Cooking the flour in the fat long enough removes its raw taste and lets it thicken the sauce smoothly. Adding the gravy too early can leave lumps or a pasty flavour.

Swap the onion

How well each one fits the dish's main ingredients (butter, flour, mustard, port wine, pepper):

Shallotfits better
Horseradishfits better
Chivefits better
Onionthe original

Fit is the average pairing score against butter, flour, mustard, port wine, pepper. 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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Gravy or Sauce for a Goose