Heat oven to 350°F. Fit crust into a 9-inch tart pan; prick bottom with a fork.

Bake the crust for 10 minutes, then let it cool slightly.

Beat mascarpone and sugar until smooth. Mix in eggs, lemon zest, lemon juice, vanilla, and salt.

Pour the filling into the crust.

Bake for 25–30 minutes, until the center barely jiggles.

Cool completely; chill at least 1 hour. Dust with powdered sugar before slicing.