Preheat oven to 350°F. Lightly grease a 12-cup muffin tin.
Combine flour, powdered sugar, and salt in a bowl. Cut in cold butter until sandy.
Stir in vanilla and just enough ice water to form a soft dough.
Press dough into cups, pushing up the sides evenly.
Chill pan 15 minutes to help prevent shrinkage.
Bake shells 12 to 15 minutes until lightly golden. Cool in the pan.
Whisk sugar, lemon zest, cornstarch, and salt in a saucepan.
Whisk in lemon juice and egg yolks until smooth and fully combined.
Cook over medium heat, stirring constantly, until thick and bubbling, 5 to 7 minutes.
Remove from heat and stir in butter until silky and glossy.
Spoon warm curd into cooled shells and smooth the tops.
Chill 1 hour to set. Garnish with berries, whipped cream, and a dusting of sugar.