Preheat your oven to 350°F (175°C).

In a medium saucepan over low heat, melt ½ cup of unsalted butter until it’s completely liquid and glossy. Let it cool slightly before adding to mixing bowl.

Combine the melted butter and 1 cup of granulated sugar in a mixing bowl, stirring until smooth. Crack in 2 eggs one at a time, mixing thoroughly. Add 1 teaspoon of vanilla extract.

In a separate bowl, whisk together 1 cup of all-purpose flour, ⅓ cup of unsweetened cocoa powder, ½ teaspoon of salt, and ½ teaspoon of baking powder.

Gently fold the dry ingredients into the wet mixture using a spatula until just incorporated.

Pour the brownie batter into a greased 9x13 inch baking pan and bake for 25-30 minutes. Check for doneness with a toothpick.

Cool the brownies completely on a wire rack for about 30-45 minutes.

In a mixing bowl, combine 2 cups of powdered sugar, 2-3 tablespoons of milk, and a few drops of green food coloring to prepare the frosting.

Spread the green frosting generously over the cooled brownies.

Insert the chocolate ice cream cones upside down into the frosted brownies as witch hats.

Sprinkle Halloween-themed decorations atop the brownies, cut into squares, and serve.