Mix flour, salt, and sugar in large mixing bowl and cut in butter until it resembles course crumbs.
Beat the egg yolk with vanilla and water and pour into flour mixture. Toss with a spatula until dough clumps together. If needed, add one more tablespoon water. Wrap in plastic wrap and chill at least 2 hours or up to 3 days.
Preheat the oven to 425 degrees F. Roll out the dough until 1/8 inch thick. Stamp out circles of the dough into tart pans, or use a muffin pan.
Place 1 tablespoon of jam in each tart. The jam should just cover the bottom of the tart. Decorate the top of the tarts with cutouts from leftover dough. Bake the tarts for 20-25 minutes or until golden. Cool completely before removing tarts from pan.