Preheat your oven to 350°F (175°C). Grease a 9x13 inch baking pan or line it with parchment paper.

Whisk together the unsweetened cocoa powder, all-purpose flour, granulated sugar, and salt in a large bowl.

Mix the melted unsalted butter with the large eggs in another bowl until smooth. Gently fold this mixture into your dry ingredients.

Pour the brownie batter into the prepared pan, spreading it evenly. Bake for 25-30 minutes, or until a toothpick inserted comes out clean.

Cool brownies completely in the pan. Frost with green-tinted frosting and decorate with sprinkles.