Sift the flour, baking soda, and salt into a medium bowl. Set aside.
Add the cocoa powder, molasses, and warm, melted butter to a large bowl and stir to mix together.
Stir (1 cup) sugar into the butter mixture, followed by the egg, vanilla extract, and espresso powder. Stir between each addition.
Add the dry ingredients to the wet ingredients and stir to form a dough.
Add the peppermint white chocolate chips and the chocolate chips and mix well to distribute them into the dough.
Cover bowl with plastic wrap and place in fridge to chill for at least one hour. (Or up to 3 days.)
When ready to bake cookies, preheat oven to 180C/350F/Gas 4.
Place rolling sugar into a small bowl.
Scoop the cookie out and roll into dough balls (about 1").
Roll the dough balls in the sugar and make sure they are well coated.
Place the sugar-coated cookie balls 2" apart onto a cookie sheet lined with parchment paper or a silicone baking mat.
Put one cookie sheet in the oven at a time. Bake for 12-14 minutes, or until cookies are puffed, centers are set and are starting to form cracks. Do not overbake!
Allow cookies to cool on the cookie sheet for 5 minutes before transferring to a wire rack to cool completely.