1-Getting Started: Preheat oven to 350°F. Prepare three 6-inch or two 8-inch round cake pans with nonstick spray and parchment paper rounds to prevent sticking. In one bowl, whisk together 1 3/4 cups all-purpose flour, 3/4 cup Dutch process cocoa powder, 1 1/2 teaspoons baking powder, 1 teaspoon baking soda, and 1/2 teaspoon salt until well combined.

2-Getting Started: In another bowl, whisk 1 3/4 cups granulated sugar with 1/2 cup canola or vegetable oil until smooth. Add 2 large eggs, one at a time, along with 2 teaspoons vanilla extract and 1/4 teaspoon peppermint extract, mixing thoroughly each time. This step incorporates air for a lighter cake.

3-Mixing and Baking: Alternately add the dry ingredients and 3/4 cup buttermilk into the wet mixture, starting and ending with the dry ingredients. Finish by stirring in 3/4 cup hot water the batter will be thin, which is normal. Pour the batter evenly into your prepared pans and bake for 35-40 minutes, or until a toothpick inserted in the center comes out clean.

4-Mixing and Baking: Let the cakes cool in the pans for 30 minutes, then transfer them to wire racks and chill in the refrigerator for 1 hour. For the buttercream, whip 1 1/2 cups unsalted butter until smooth, then gradually add 4 cups powdered sugar, 1 to 2 tablespoons milk, and 1 teaspoon peppermint extract.

5-Finishing Touches: Add 3 to 4 drops of green gel food coloring for a light pastel shade, and optionally a drop of blue and half a drop of brown for a natural mint look. Fold in 4 oz finely chopped dark or semisweet chocolate. Level the cake layers if needed, spread buttercream between them, and chill for 30 minutes before applying a thick layer around the cake. Smooth gently with an offset spatula and serve. For variations, like a sheet cake, try baking in a 9×13 pan as shared in related recipes.