Dissolve the yeast in the warm water for 5 minutes. Add the bread flour, milk, sugar, melted butter, and salt to the dissolved yeast and water and mix the dough on medium speed for about 2 minutes. If the dough is too sticky, add 1 tablespoon of extra flour at a time, until the dough is just firm enough to fold a shape.

Shape dough into a ball and loosely cover it with saran wrap. Allow it to rest at room temperature for 30 minutes. Roll the dough into a 10-inch by 15-inch rectangle, and then cover it loosely and allow it to rise for 40 minutes.

Brush the rectangle with the softened butter and then fold the dough into thirds, like a letter. Roll the long, thin rectangle back into the original 10-inch by 15 shape. Fold the dough into thirds, again, and then cover the dough with plastic wrap and allow it to rest in the refrigerator for 1 hour. Repeat this process one more time.

(If you would like to skip these steps you could very easily use a pre-made croissant dough).

Using a sharp knife, cut the dough crosswise into 12 rectangles. In a blender mix Cool Brew Mocha Concentrate (I used 4 fl. oz) and chopped chocolate. Spoon out two teaspoons of the chocolate mixture across one of the short ends of the rectangle and fold that third of the dough over the chocolate, toward the center. The chocolate mixture will be chunky- this is ok. Repeat the process on the opposite side of the dough, folding it over and tucking the end under to create a cylindrical shape.

Arrange each finished pain au chocolate on a lightly greased baking sheet with at least 1 1/2 inches between each pastry. Cover them loosely with plastic wrap and allow them to rise for 45 minutes to 1 hour, until they are nearly doubled in size.

Preheat the oven to 400F. Whisk the egg and 2 tablespoons milk together to make an egg wash. Brush the egg wash across the surface of each pastry. Bake the pan au chocolate for 12 to 14 minutes, until they are puffed and golden brown.