Skip to main content
Main

Boiled Onions

A dish of onions boiled, then simmered with milk, flour, butter, salt, and pepper.

From an old cookbook · modernised transcription
From a historical cookbook (Internet Archive) · 7 ingredients
Jump to recipe ↓

Why it works: Milk and butter 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

Prepare the onions

  1. Peel the onions and soak them in cold water for 1 hour.

  2. If the onions are large, halve them.

  3. Cook the onions in boiling water with a pinch of baking soda for 15 minutes.

  4. Drain the water and rinse the onions with boiling water.

Cook and finish

  1. Return the onions to the stove in boiling water, add salt, and cook until very tender.

  2. Just before serving, pour off the water.

  3. In a separate bowl, mix 1 cup of milk with 2 teaspoons of flour until smooth.

  4. Add the flour mixture and 1 tablespoon of butter to the onions.

  5. Season with salt and pepper to taste.

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. Milk + buttertop 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. Flour + buttertop 12% of all pairs
    Smell alikelow
    Cooked together124,287 recipes

    Shared aroma: isobutyraldehyde (malty, green).

  4. Milk + flourtop 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).

Flour and butter 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

Onions
Main vegetable; long cooking turns them soft, sweet and tender.
Milk
Forms the liquid base of the creamy sauce, adding moisture and richness.
Flour
Thickens the milk into a smooth sauce as its starch swells when heated.
Butter
Adds fat and flavour, giving the sauce a smooth, rich mouthfeel.
Baking soda
Raises the cooking water's pH, helping onions soften faster and turn translucent.

The step that matters

Cook the onions until very tender. Onions need long, gentle cooking to break down their fibres fully. Stopping early leaves them firm and sharp-tasting, so check for softness rather than relying only on the timer.

Swap the onion

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

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

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