Preheat the oven to 350 F and spray a mini cupcake pan with cooking spray. Set aside.

In a small bowl, whisk together the flour, baking powder, and salt. Set aside.

In a medium bowl, beat the butter and sugar until light and fluffy.

Add the egg and vanilla, beating until combined.

Gradually add the flour, beating on low speed. Add the milk and beat until combined.

Add a few drops of green gel food coloring and beat until fully incorporated.

Transfer the dough to the prepared cupcake pan and bake for 8-10 minutes or until a toothpick inserted in the center of a cupcake comes out clean.

Let cool for 10 minutes in the pan before transferring to a wire rack to cool completely.

In a medium bowl, beat the butter until creamy.

Add the powdered sugar, beating on low speed until just combined.

Add the milk and lemon extract. Beat on medium high speed until light and fluffy.

Add a few drops of yellow gel food coloring and beat until fully incorporated.

Transfer the frosting to a piping bag fitted with a large round piping tip.

Pipe a swirl of frosting onto the tops of the cupcakes.

Dip a clean paintbrush into the edible gold cake dust and sprinkle it onto each cupcake.