In a mixing bowl, add Butter (1/2 cup), Granulated Sugar (1/4 cup), and Brown Sugar (1/2 cup). Stir together. Add Large Egg (1) and Vanilla Extract (1 teaspoon) and whisk until combined.
In a separate bowl, add Unsweetened Cocoa Powder (1/3 cup), All-Purpose Flour (1 cup), Baking Soda (1/2 teaspoon), and Salt (1/4 teaspoon). Stir to combine.
Combine the wet and dry ingredients and mix until smooth.
Add Semi-Sweet Chocolate Chips (1/2 cup) and White Chocolate Chips (1/2 cup). Fold them gently into the batter.
Line a baking sheet with parchment paper. Place spoonfuls of cookie dough onto the paper.
Bake at 350 degrees F (180 degrees C) for 10 minutes.
Allow cookies to cool before serving. Enjoy!