Preheat your oven to 350°F (175°C). Grease and flour two 9-inch round cake pans.
In a medium bowl, whisk together the flour, baking powder, and salt. In a large bowl, cream the 1/2 cup of unsalted butter and granulated sugar until light and fluffy. Beat in the eggs one at a time, then stir in the milk and 1 teaspoon of vanilla extract. Gradually add the dry ingredients to the wet ingredients, mixing until just combined.
Divide the batter evenly between the prepared cake pans. Bake for 25-30 minutes, or until a toothpick inserted into the center comes out clean. Allow the cakes to cool in the pans for 10 minutes, then transfer to a wire rack to cool completely.
To make the frosting, in a large bowl, beat the 1 cup of unsalted butter until smooth and creamy. Gradually add the confectioners' sugar and 1 teaspoon of vanilla extract, beating until light and fluffy.
Divide the frosting into two bowls. In one bowl, add green food coloring and mix until the desired shade of green is achieved. In the other bowl, add yellow food coloring and mix until the desired shade of gold is achieved.
When coloring the frosting, be sure to add the food coloring gradually and mix well to achieve the desired shades. Additionally, you can use a combination of green and yellow food coloring to create a more natural-looking green hue.
For a more vibrant cake, consider using a darker green and a richer gold color. Finally, be sure to allow the cakes to cool completely before frosting to prevent the frosting from melting.
This green and gold cake is a harmonious union of taste, nutrition, and environmental stewardship - a delicious reflection of the power of mindful, sustainable baking.