Skip to main content
Main

Boiled Onions

Boiled onions simmered in salted water, then served with butter, flour, and milk sauce.

From an old cookbook · modernised transcription
From a historical cookbook (Internet Archive) · 6 ingredients
Jump to recipe ↓

Why it works: Butter and milk are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 81,283 recipes. Both carry (z)-4-heptenal, which smells biscuit, cream. The science ↓

Boiled Onions

Ingredients

Directions

Boil the onions

  1. Peel the onions and boil them in salted water for 35 to 40 minutes.

  2. Remove the onions with a skimmer and drain them.

Make the sauce

  1. In a saucepan, stir 2 teaspoons of butter to a cream, then add 1 tablespoon of flour and ⅓ teaspoon of coarse sea salt.

  2. Slowly add ⅓ cup of boiling milk, stirring constantly until smooth, and cook for a few minutes.

Serve

  1. Alternatively, serve the onions with salt, pepper, and a small lump of butter in each onion.

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.

  1. Butter + milktop 7% of all pairs
    Smell alikemoderate
    Cooked together81,283 recipes

    Shared aroma: (z)-4-heptenal (biscuit, cream).

  2. Onion + peppertop 11% of all pairs
    Smell alikemoderate
    Cooked together68,474 recipes

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

  3. Butter + flourtop 12% of all pairs
    Smell alikelow
    Cooked together124,287 recipes

    Shared aroma: isobutyraldehyde (malty, green).

  4. Flour + milktop 14% of all pairs
    Smell alikelow
    Cooked together78,219 recipes

    Shared aroma: isobutyraldehyde (malty, green).

  5. Onion + buttertop 15% of all pairs
    Smell alikemoderate
    Cooked together42,912 recipes

    Shared aroma: decanal (soap, orange peel).

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

White onions
Boiling softens the onions and mellows their sharp flavour, making them tender and mild.
Butter
Adds richness and fat, carrying flavour and giving the sauce a smooth, creamy mouthfeel.
Flour
Its starch thickens the milk as it heats, turning the liquid into a smooth sauce.
Milk
Forms the liquid base of the sauce, adding creaminess and mild sweetness.

The step that matters

Adding the boiling milk to the butter and flour. Adding the hot milk slowly while stirring constantly keeps the flour evenly dispersed, so the sauce becomes smooth instead of lumpy as the starch thickens.

Swap the onion

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

  1. Potatofits better
  2. Capsicumfits better
  3. Chivefits better
  4. Onionthe original

Fit is the average pairing score against butter, flour, milk, 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.

You might also like

Tomato SoupTomato Soup526 recipesBrown BreadBrown Bread461 recipesMutton BrothMutton Broth292 recipesYorkshire PuddingYorkshire Pudding264 recipes