Chocolate Pretzels

1. Pour the boiling water into a small heatproof bowl. Stir in cocoa and espresso powder until dissolved. Set aside. In another bowl, using an electric mixer fitted with the paddle attachment, beat together butter and granulated sugar on medium speed until creamy. Add in vanilla and salt. Reduce speed to medium-low. Add in the egg followed by the cocoa mixture. Gradually add in flour, and mix until dough becomes smooth. Place dough on a piece of plastic wrap and form into a square. Wrap and refrigerate until cold, about 30 minutes.
2. Preheat oven to 325 F. Divide dough into 24 equal pieces. Roll each piece into a 12-inch-long rope. Twist each rope into a pretzel shape. With either end of the rope suspended in the air, drop the curve of the dough on the pan, twist the ends once, and overlap with the bottom curve. Place the pretzels 1 inch apart on a baking sheet that you’ve lined with parchment paper or a Silpat.
3. Whisk together egg yolk and 1 teaspoon water. Lightly brush pretzels with egg wash and sprinkle with sanding sugar (or turbinado). Bake cookies until dry, about 30 minutes. Allow to cool completely before serving. Store in an airtight container for up to a week.

Recipe adapted from Martha Stewart.