01 -
Heat oven to 375°F (190°C) with baking sheet on middle rack.
02 -
Brush 4 (8-oz) ramekins with softened butter using upward strokes, then coat with sugar. Discard excess sugar.
03 -
Bring milk to simmer. Separately, whisk yolks with 3 tablespoons sugar until pale, then whisk in flour. Temper with hot milk, then cook mixture until thickened. Stir in vanilla.
04 -
Beat egg whites with salt until foamy. Gradually add remaining sugar and whip to stiff peaks.
05 -
Gently fold whipped whites into slightly cooled yolk mixture until just combined.
06 -
Divide between prepared ramekins and place on hot baking sheet. Bake 25-30 minutes until puffed and golden.
07 -
Dust with powdered sugar and serve immediately while puffed.