Prepare the Brownies:

1. Preheat the Oven: Set your oven to 350°F (175°C). Line an 8×8-inch baking pan with parchment paper.
2. Mix Wet Ingredients: In a large bowl, whisk together melted butter, sugar, eggs, and vanilla extract until smooth.
3. Combine Dry Ingredients: In a separate bowl, sift cocoa powder, flour, salt, and baking powder. Stir the dry ingredients into the wet mixture until just combined.
4. Bake the Brownies: Pour the batter into the prepared pan and spread evenly. Bake for 25 minutes or until a toothpick inserted in the center comes out with a few moist crumbs.
5. Cool Completely: Let the brownies cool in the pan for at least 15 minutes before cutting into squares.

Decorate the Bunny Brownies:

6. Prepare the Bunny Ears: Cut marshmallows in half diagonally, then dip the sticky side into pink sanding sugar to create inner ears.
7. Frost the Brownies: Spread a thin layer of white chocolate or vanilla frosting on each brownie.
8. Add the Bunny Face: Place two mini chocolate chips for eyes and a pink candy pearl for the nose.
9. Attach the Bunny Ears: Press two marshmallow ears onto the top of each brownie.
10. Sprinkle with Coconut: Lightly press shredded coconut onto the frosting for a fluffy bunny fur effect.