01 - Preheat oven to 350°F and line a 12-cup muffin tin with paper liners.
02 - In a medium bowl, sift together flour, cocoa powder, baking powder, baking soda, and salt.
03 - In a large bowl, whisk eggs and sugar until light and fluffy. Add milk, vegetable oil, and vanilla extract; blend until combined.
04 - Gradually add dry ingredients to wet mixture, stirring until just incorporated.
05 - Divide batter evenly among cupcake liners. Bake for 16-18 minutes, or until a toothpick inserted in the center comes out clean. Cool completely.
06 - Beat butter until creamy. Gradually mix in powdered sugar and cocoa powder. Add vanilla and 2 tbsp milk; beat until fluffy, adding more milk if needed for spreading consistency.
07 - Frost cooled cupcakes generously.
08 - Carefully twist Oreos apart, keeping cream on one side. Place two halves cream-side up on each cupcake.
09 - Press a brown candy on each eye for pupils. Position an orange or yellow candy below the eyes as the beak. Optionally, use Oreo halves without cream on top corners as eyebrows.