1-Getting started: First, preheat your oven to 410°F (210°C) and line a baking sheet with parchment paper to make cleanup easy and prevent sticking.

2-Cream together the cold butter, brown sugar, and granulated sugar: for at least 4 minutes until the mixture becomes light and creamy this step is key for that perfect texture.

3-Add the eggs and vanilla extract: mixing for another minute to fully incorporate them.

4-Fold in the cocoa powder, cake flour, all-purpose flour, cornstarch, baking soda, and salt: until everything is well combined, creating a rich dough base. Stir in the chocolate chips, mini marshmallows, and chopped cashews to add those signature Rocky Road elements. Shape the dough into balls weighing 5 to 6 ounces each and place them on the prepared baking sheet, then top each ball with a few extra chocolate chips and marshmallows, pressing them lightly into the dough.

5-Bake the cookies: Bake the cookies for 9-11 minutes until they have crispy edges and a gooey center, watching carefully to avoid overbaking. Right after removing them from the oven, use a spatula to gently press the edges toward the center to keep the marshmallows from spreading too much. Let the cookies rest on the baking sheet for 15 minutes before moving them, allowing them to set perfectly for the best results.