This recipe was handed down to me many years ago from my sister-in-law who grew up in the Virgin Islands. The tart pastry is wonderfully flaky and buttery and very versatile. It's become my go to tart dough. The filling is easy and a perfect balance of sweet and tart. Also, Mrs. Percival actually did exist in the islands —GabriellaVV
Preheat oven to 350F.
In food processor, combine flour, frozen butter cubes, salt and sugar and lemon zest until texture resembles coarse cornmeal, with butter pieces no larger than small peas.
Combine egg yolk, vanilla and cold water. Add the egg mixture to the food processor and pulse just until the dough pulls together. Add more ice water if necessary.
Mix guava paste and 1 tablespoon lemon juice in blender until smooth.
Divide dough in half. Roll out and fancy cut half of dough. Rollout and place other half of dough in pan. Spread paste over dough. Crisscross dough strips over paste and brush with egg white. Sprinkle with crystallized or demerara coarse sugar.
Bake in 350 oven for 1 hour or until golden brown.