These look far more difficult than they actually are, although the rolling process can be a bit iffy. Make sure your dough is well-refrigerated. They come out with a crisp yet airy texture.
Chocolate Orange Pinwheels
1 c all-purpose flour
1/4 tsp baking powder
1/8 tsp salt
1 oz semisweet chocolate, chopped
1/2 c unsalted butter, at room temperature
1/2 c granulated sugar
1 large egg, separated
1 tsp vanilla extract
1 tsp grated orange-zest
2 tsp Dutch-process cocoa powder
1. In a bowl, sift together the flour, baking powder, and salt. Set aside. Place the chocolate in the top of a double boiler placed over hot, barely simmering water. Heat, stirring often, until the chocolate melts. Remove from over the water and set aside to cool slightly.
2. In a large bowl, combine the butter and sugar. Beat on medium speed until smooth, about 3 minutes. Add the egg yolk and vanilla and beat on low speed until blended. Add the dry ingredients and mix until incorporated and the dough is smoothing.
3. Divide the dough in half. Put one-half of the dough in a separate bowl and stir in the orange zest. Add the melted chocolate and cocoa powder to the dough remaining in the large bowl and mix on low speed until completely blended into the dough. Gather up each portion, wrap in plastic wrap, and refrigerate until firm, about 45 minutes.
4. Remove the dough from the refrigerator. One at a time, place each dough portion between 2 sheets of waxed`paper and roll out into a rectangle 10 by 5 inches and about 1/8 inch thick. Remove the top piece of waxed paper from each rectangle. In a small bowl, using a fork, beat the egg white until foamy. Brush it lighting over the top surface of the chocolate dough. Using the waxed paper, flip the chocolate dough onto the orange dough and press the doughs together. Peel off and discard the top piece of waxed paper. Trim the dough edges evenly. Roll up the 2 layers of dough into a tight log, removing the remaining piece of waxed paper as you roll. Gently press the seam along the roll to seal it. Trim the ends evenly. The roll should be about 9 inches long. Wrap in plastic wrap and refrigerate until firm, at least 1 hour or overnight.
5. Position a rack in the middle of the oven and preheat to 350oF. Line 2 rimless baking sheets with parchment paper. Unwrap the log and slice into slices about ¼ inch thick. Place 1 inch apart on the prepared baking sheets.
6. Bake the cookies, 1 sheet at a time, until the edges just begin to turn slightly golden about 8-12 minutes. Let the cookies cool on the baking sheets for 5 minutes, then transfer them to wire racks to cool completely.
Makes about 30 cookies