Pink grapefruit doughnut glaze

Yield ≈ 305 g·Keeps 3 days, room temp·Basis % · sugar = 100·Contains None·Source House formula · Original

Ingredient	%	Grams
Confectioners’ sugar · sifted	100.0	240
Pink grapefruit juice · fresh	18.8	45
Pink grapefruit zest † · 1 fruit	1.7	4
Light corn syrup · for shine	6.3	15
Fine salt	0.4	1
Total	127.1	305

Scale by weight: target ÷ 1.271 = sugar; then × each %. Juice is a range, 40–55 g. Sets ivory, not pink; the zest carries the flavour. † Zest doesn’t scale in a straight line past 2×.

Method

1
Zest. Rub into the sugar until damp.
1 min
Fingers
2
Whisk. Juice, syrup, salt; until smooth.
1 min
Glossy
3
Adjust. +5 g juice thins; +15 g sugar thickens.
—
Ribbon, 3 s
4
Glaze. Dip warm tops; set until matte.
20 min
Warm bake

24 cake doughnuts at ≈ 12 g, or one Bundt. Milder and more bitter than lemon; the bitterness is the point. Rewhisk to reuse; loosen with juice.