Preheat oven to 275°F (135°C).

Lightly grease a 10 x 15 inch jellyroll pan (or 9x13 inch cake pan).

In a large mixing bowl, beat softened butter, powdered sugar, and salt together until light and fluffy.

Beat in the egg yolk and almond and vanilla extracts.

Stir in the cardamom seeds.

Gradually stir in the flour, 1/2 cup at a time, blending well after each addition.

Spread the dough evenly over the bottom of the prepared pan.

In a small bowl, lightly whisk the egg white until frothy.

Pour the frothy egg white over the dough and spread it evenly.

Sprinkle the finely chopped almonds over the dough and press them lightly into the surface with the back of a spoon.

Bake for 50 to 60 minutes, or until golden brown.

Immediately use a sharp knife to cut the baked dough into 40 finger-shaped cookies (4 across, 10 down).

Cool in the pan on a rack for 15 minutes.

Carefully remove the cookies from the pan as they are fragile.

Cool completely on racks.

Keep in an airtight container for up to one week, or freeze for up to three months if well-wrapped.