Steps
1. Preheat oven to 350°F (175°C).
2. In a small bowl, whisk the egg and sugar until light and fluffy.
3. Add milk and melted butter, mix well.
4. Sift in flour and baking powder, gently fold to combine.
5. Add a few drops of yellow food coloring and mix until the batter is evenly colored.
6. Pour batter into a small greased round cake pan or ramekin.
7. Bake for 12-15 minutes or until a toothpick inserted comes out clean.
8. Let the cake cool completely on a wire rack.
9. Once cooled, use a round cookie cutter or knife to shape the cake into a square.
10. Using icing pens or colored frosting, carefully decorate the cake to create SpongeBob’s face and details: big eyes, nose, mouth, and tie.
11. Add small edible decorations for eyes if desired.
12. Serve and enjoy your SpongeBob themed mini sponge cake!