Preheat your oven to 350°F (175°C) and grease an 8x8-inch baking dish. In a large mixing bowl, cream together the softened butter, granulated sugar, and brown sugar until fluffy and light in color. Add the eggs and vanilla extract, mixing well until combined. Gradually sift in the all-purpose flour, cocoa powder, and salt, stirring until just combined to keep the batter fudgy.

Pour the brownie batter into the prepared baking dish and smooth it into an even layer with a spatula. Bake in the preheated oven for 25-30 minutes, or until a toothpick inserted into the center comes out with a few moist crumbs.

Once baked, allow the brownies to cool in the pan for at least 15 minutes before transferring them to a wire rack to cool completely.

While the brownies are cooling, prepare the frosting by creaming together softened butter and powdered sugar. Gradually add the vanilla extract and milk, blending until smooth. Slowly incorporate the remaining powdered sugar until you achieve a thick, spreadable consistency.

Divide the frosting into small bowls and add food coloring to each bowl, mixing until the colors are vibrant. Set aside as you prepare to frost the cooled brownies.

Spread the colored frosting over the cooled brownies using a spatula, creating a smooth layer. Sprinkle colorful sprinkles on top.

Place a chocolate bunny on each brownie square, gently pressing down to secure them in place.