Why it works: Flour and butter are a kitchen classic. They rank in the top 12% of all ingredient pairs, and cooks put them together in 124,287 recipes. Both carry isobutyraldehyde, which smells malty, green. The science ↓
French Thickening, or Brown Roux
Ingredients
Directions
Make the clarified butter
Dissolve half a pound of good butter over gentle heat.
Remove from heat, skim, and let settle.
Make the roux
Pour the clarified butter into a very clean frying pan and place over a slow, clear fire.
Place about seven ounces of fine dry flour in a dredging box.
Gradually add the flour to the butter, shaking the pan often as it is added.
Keep the mixture constantly stirred until it acquires a clear light-brown colour.
Pour the roux into a jar and stir a spoonful or two into boiling soup or gravy as needed.
If the butter is not clarified, it will absorb an additional ounce of flour; ensure the flour is fine and dry.
For large-scale cooking, the roux may be made in a well-tinned stewpan over a coal fire, placed high above and guarded from smoke.
Nutrition, whole recipe (rough)
What these numbers assume: 2 portions
| Ingredient | Portion assumed | kcal |
|---|---|---|
| Flour | 1 cup (125g) all-purpose | 455 |
| Butter | 1 tbsp (14g) | 102 |
One typical portion per ingredient; the recipe's quantities are not counted. A rough guide only, not for medical or dietary planning.
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. See the original page.
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.
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Flour + buttertop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
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
- Flour
- Thickens the butter into a roux that gives body to soups and gravies.
- Butter
- Carries the flour and adds richness, with its fat coating the starch grains.
The step that matters
Keep the mixture constantly stirred until it acquires a clear light-brown colour.. Flour toasts unevenly and can scorch on the pan bottom over heat; constant stirring keeps the roux cooking evenly, and the colour deepens as it toasts, so it must be stopped at the right shade.
“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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