Peel the pineapple, remove the eyes and core, and chop it to make 1 1/2 cups.

In a saucepan, combine the chopped pineapple, sugar, and 1/3 cup of water.

Bring the mixture to a boil, then reduce the heat to medium and cook until thickened, stirring occasionally. Watch closely during the last 5 minutes to prevent sticking. Cool completely.

In a bowl, cut the butter into the flour until the mixture is crumbly.

Add the egg yolks and vanilla and stir until well combined.

Sprinkle 1 tablespoon of cold water over part of the mixture, gently toss with a fork, and push it to the side of the bowl.

Repeat this process until all the mixture is moistened.

Form the dough into a ball, cover it, and chill in the refrigerator for 1 hour.

Divide the dough in half.

On a lightly floured surface, roll each half into a 10x10 inch square.

Cut each square into sixteen 2 1/2 inch squares.

Spoon about 1 teaspoon of pineapple filling diagonally in the center of each square.

Bring up two side corners and overlap them slightly to enclose the filling.

Place the pastries on an ungreased baking sheet.

Brush lightly with beaten egg white to seal.

Bake in a preheated 400-degree oven for 10 to 12 minutes, or until golden brown.

Cool the pastries on a wire rack before serving.