01 - Fill steamer with water and bring to a simmer. Line cupcake molds or silicone cups with paper liners.
02 - Whisk together flour, baking powder, baking soda, and salt in a bowl until well blended.
03 - Beat eggs and sugar in a large bowl until pale and thick. Add milk, melted butter, and vanilla extract. Mix until smooth.
04 - Gradually fold dry ingredients into wet mixture until just combined. Avoid overmixing to maintain texture.
05 - Divide batter and fold in food coloring if desired. Pour batters in layers or swirl for marbled effect.
06 - Spoon batter into prepared cupcake molds, filling each about ¾ full to allow room for rising.
07 - Place molds in steamer with space between them for circulation. Cover lid with clean cloth to prevent condensation from dripping.
08 - Steam over medium heat for 12-15 minutes until toothpick inserted comes out clean and tops have bloomed.
09 - Remove from heat and let cool slightly. Decorate with sprinkles, edible flowers, or chocolate chips as desired.