Mix flour, sugar, and salt in a bowl.
Add grated frozen butter and mix until crumbly.
Gradually add ice water one tablespoon at a time, mixing until dough forms.
Form dough into a disk, wrap in plastic, and chill for 30 minutes.
Preheat oven to 350°F (175°C).
Roll out dough and press it into a tart pan.
Prick the base with a fork to prevent bubbling.
Bake crust for 15 minutes, then cool slightly.
Beat cream cheese, sour cream, and sugar until smooth.
Add egg yolk, salt, vanilla extract, and lemon zest, mixing until creamy.
Pour filling into the baked crust.
Bake tart for 10–15 minutes until filling is set.
Cool completely then chill the tart for 1 hour.
Arrange fresh strawberries neatly on top of the tart.
Heat jam with water until smooth, then brush gently over strawberries for a glossy finish.
Chill slightly before slicing and serving.