-
sift the
flour, baking powder, and salt into a medium
bowl. Beat the butter and vanilla sugar in a
large bowl with an electric mixer at high speed
until creamy.
-
Mix in the
dry ingredients to form a stiff dough. Lightly
dust a surface with confectioners' sugar and
divide the dough in half.
-
Knead the
cocoa powder into one half of the dough until
well blended. Wrap each dough portion in plastic
wrap and refrigerate for at least 30 minutes.
-
Cut each
chilled portion in thirds and form into long
logs 1 inch (2.5 cm) in diameter. Press the
edges of the logs to make them into even-sided
oblongs.
-
Arrange the
three chocolate logs and the three plain logs on
top of each other in a checkerboard pattern.
-
To do so,
place one light log next to one dark log, then
set a dark log on top of the light log to make a
roll with alternating chocolate and plain
sections.
-
Seal the
sections together by brushing them with a little
egg white. The dough will now be rectangular in
shape. Wrap in plastic wrap and refrigerate for
at least 1 hour.
-
Preheat the
oven to 375°F/190°C/gas 5. Butter two large
cookie sheets. Slice the dough 1/4 inch (5 mm)
thick and place 1 1/2 inches (4 cm) apart on the
prepared cookie sheets.
-
Bake for
10-15 minutes, or until lightly browned and the
edges are firm. Transfer to racks to cool.