Shortbread Lab
Butter, sugar, flour: how far recipes stray from the Scottish 1:2:3.
433 recipes from 122 sites, each reduced to grams and written as baker's percentages: grams of each ingredient per 100 g of flour, so a small recipe and a double batch line up. Below: the typical pan, how far recipes stray from it, and a page for every recipe with a link to the original.
Recipes
433
from 122 sites
Typical flour
250 g
about 2 cups
Oven
350°F
175°C · median of 389
Bake time
18 min
most 13 to 23 min
The median of all 433 recipes for each ingredient, scaled to 250 g of flour. No single recipe is exactly this: each line is the middle of its own distribution. “Most recipes” means the middle half, from the 25th to the 75th percentile.
| Ingredient | Grams |
|---|---|
| FlourThe scale for everything else | 250 gabout 2 cups |
| ButterMost recipes use 175 to 225 g | 200 gabout 1 cup |
| SugarMost recipes use 85 to 130 g | 100 gabout 1/2 cup |
| Starch83% use none; the rest mostly 28 to 75 g | none |
| Salt36% use none; the rest mostly 1 to 3 g | 1 g |
Bake350°F (175°C) for about 18 minutes.
Volumes are approximate: flour at 125 g a cup, sugar 200 g, butter or oil 225 g.
Each dot is a recipe, placed by grams of the ingredient per 100 g of flour (100% would be as much as the flour). The shaded band is the middle half of recipes and the line is the median.
median 81% · most 69 to 91%
Butter is the point. The Scottish ratio is two parts butter to three of flour; more makes a shorter, more melting biscuit.
range 40 to 126%
median 40% · most 33 to 51%
Sugar at about half the butter. Powdered sugar gives a finer, sandier crumb than granulated.
range 11 to 100%
median 0% · 83% use none
Cornstarch or rice flour in place of some flour means less gluten and a more tender snap.
range 0 to 50% · those that use some, mostly 11 to 29%
median 0.4% · 36% use none
Salt, often none when the butter is salted.
range 0 to 2.9% · those that use some, mostly 0.4 to 1.2%
Measured by how far apart the 25th and 75th percentile recipes are. The widest gaps are where the choice of recipe matters most.
Recipes agree most on butter: butter 69 to 91% for the middle half.
423 of the recipes come in 4 languages with enough of each to compare: English 337, French 39, German 30, Dutch 17.
English recipes whose titles use a word, against the ones that do not. What recipe writers do when they pick the word, not proof that it makes the texture.
Recipes called “easy” (11) use about the same amounts as the rest on every ingredient measured here.
Recipes with “whipped” in the title: most add starch (81% vs 15% use some); more butter (114% vs 83%).
“whipped” (11)the rest (326)middle half of all
Starch · share using anyrecipes with whipped in the title 81% vs the rest 15%
Butterrecipes with whipped in the title 114% vs the rest 83%
53 shortbread recipes have 50 or more reader ratings. A rating count says how many people rated a page, which follows its traffic more than its quality. Against the other 380, medians per 100 g of flour, compared within each language:
On no ingredient do the most-reviewed recipes differ from the rest by more than chance would explain.
50+ ratings (53)the rest (380)middle half of all
Butterthe most-reviewed recipes 89% vs the rest 80%
Sugarthe most-reviewed recipes 40% vs the rest 39%
Starchthe most-reviewed recipes 0% vs the rest 0%
Saltthe most-reviewed recipes 0.5% vs the rest 0.4%
389 of 433 recipes state an oven temperature, and 56% of those bake at 350°F (175°C). The middle half bake at 325 to 350°F. The other 44 do not say.
413 recipes state a bake time. Taking the middle of any stated range (“55 to 65 minutes” counts as 60), the median is 18 minutes and the middle half bake 13 to 23 minutes.
The single most common pairing is 350°F for 10 to 15 minutes, with 91 of the 377 recipes that state both.
Nearest the median on every ingredient at once.
In 7 languages: English 337, French 39, German 30, Dutch 17, Spanish 4, Portuguese 3, Italian 3. Lines in other languages are read in their own units and words, and each recipe page links to the original. 122 sites in all. No site contributes more than 12 recipes.
Every ingredient line is converted to grams and grouped (butter and oil count as fat; white, brown and liquid sweeteners as sugar), then divided by the flour weight. That baker's percentage is the only comparison that holds across recipes of different sizes.
95% of the 2,823 ingredient lines got a weight. 38% of those weights were printed by the source; the rest were converted from cups and spoons with standard densities, so treat single recipes as close, not exact. Frosting, glaze, streusel and other toppings are listed on each recipe page but left out of the percentages.
A recipe outside the plausible range for any ingredient is left out rather than allowed to stretch every chart; it is usually a different dish with the same name or a misread line. Of the pages fetched, 135 were left out: 62 outside the plausible range on some ingredient (sugar 38, butter 21, salt 2, starch 1), 26 with a title that names a different dish, 20 over the 12-per-site cap, 10 with no flour, or none that could be weighed, 8 too many lines without an amount, 8 duplicates of other pages, and 1 a listing page, not a recipe page.
Every recipe page links to the original, which is where the method is. Recipe Lab does not republish instructions or photos.