Chocolate Marble Cookies

Ingredients

• 0.3 teaspoon coarse kosher salt 
• 0.3 cup dutch-process cocoa powder 
• 1 large eggs 
• 2.5 cup flour all-purpose sifted
• 0.3 teaspoon lemon extract pure
• 0.5 cup sugar 
• 48 servings sugar crystals raw
• 1 cup butter unsalted softened
• 1 teaspoon vanilla extract pure
• 1 tablespoon water 

Equipment

• bowl
• baking sheet
• baking paper
• oven
• whisk
• wire rack
• blender
• plastic wrap
• hand mixer
• rolling pin

Directions

1. In the bowl of an electric mixer fitted with the paddle attachment, cream butter and sugar until well blended, 1 to 2 minutes.
2. Add vanilla extract, lemon extract, and salt. With mixer on low speed, gradually add flour, scraping down sides of bowl.Turn dough out onto a clean work surface; it will be loose and crumbly. Knead dough by pushing small amounts away from you with the heel of your hand for 1 to 2 minutes. Divide dough in half.
3. Sprinkle cocoa powder over one of the halves. Knead until cocoa has been fully incorporated.Shape each half into 8 inch discs about 1 inch thick. Wrap the dough discs separately in plastic wrap and refrigerate at least ½ hour. After the dough is well chilled, place each half of the kneaded dough between two sheets of plastic. Using a rolling pin, roll the dough into equal sized rounds about ¼ inch thick. You may have to refrigerate the dough another ½ hour depending on room temperature and how sticky the dough became.Next, whisk together the egg and 1 tablespoon water. Peel off the plastic wrap from both pieces of dough.
4. Lay one circle out in front of you and brush it with the egg wash.
5. Lay the other circle of dough on top lining the edges up together as well as possible. I prefer to put the chocolate layer on top. But either is fine.Starting on one end roll the disc together “jelly-roll” style to form a log.
6. Cut this log in half crosswise, then roll one log out further forming a log that is about 1 ½ inches in diameter.
7. Cut this log in half crosswise and roll each half in the raw sugar crystals making sure the sugar adheres well. Repeat with remaining dough until you have four sugar coated logs.
8. Place the logs on a parchment lined tray, and refrigerate covered for at least ½ hour. They may also be frozen at this point up to one month.When ready to bake, preheat oven to 350 degrees F. Line a baking sheet with parchment paper. Slice each log into ¼-inch-thick slices; place on baking sheet.
9. Bake until done, 10 to 12 minutes.
10. Remove baking sheet from oven, and let cookies cool 2 minutes.
11. Transfer cookies to a wire rack to cool completely. Store cookies in an airtight container up to 2 days.