In a mixing bowl, combine melted butter and sugar. Mix until well combined.
Add the egg to the butter and sugar mixture, and beat until fluffy.
Sift together flour, cocoa powder, and baking soda into the egg mixture. Mix until a smooth dough forms.
Fold in the milk chocolate drops using a spatula until evenly distributed throughout the dough.
Preheat the oven to 180°C. Line a baking tray with parchment paper.
Scoop out portions of dough using an ice cream scoop and place them on the prepared baking tray, leaving space between each cookie.
Bake the cookies in the preheated oven for 10 minutes, or until the edges are set and the tops are slightly firm.
Once baked, remove the cookies from the oven and let them cool on the baking tray for a few minutes before transferring them to a wire rack to cool completely.
Once cooled, serve and enjoy these delicious homemade chocolate chip cookies with a glass of milk or your favorite hot beverage!