Begin by preparing three 8-inch round cake pans. Line each pan with parchment paper to ensure the cakes release cleanly, and lightly grease the sides for added ease. Preheat your oven to 300°F (148°C).

In a large mixing bowl, whisk together the flour, sugar, cocoa powder, baking soda, and salt until evenly combined.

Add the eggs, milk, vegetable oil, vanilla extract, orange extract, and fresh orange zest to the dry ingredients. Mix the ingredients with a spatula or electric mixer on low until they just come together into a thick, uniform batter.

Gradually pour in the fresh orange juice while mixing. Continue until the batter is smooth and free of lumps, taking care not to overmix.

Evenly divide the cake batter across the prepared pans, ensuring the layers are equal in height. Bake the cakes for 30–35 minutes, or until a toothpick inserted into the center comes out with just a few moist crumbs clinging to it.

Remove the cakes from the oven and let them cool in the pans for about 5 minutes. Carefully turn the cakes out onto wire racks and allow them to cool completely before frosting.

While the cakes cool, prepare the frosting. In a large mixing bowl, beat the room-temperature butter using an electric mixer until smooth and fluffy.

Add half of the powdered sugar along with the cocoa powder. Beat on medium speed until well combined, creating a rich, velvety base.

Mix in the orange extract, vanilla extract, fresh orange zest, and 5 tablespoons of orange juice. Beat the frosting again until it’s smooth and fragrant.

Gradually incorporate the remaining powdered sugar and continue beating until the frosting reaches a light and creamy texture. Adjust the consistency by adding more orange juice, a tablespoon at a time, until it’s perfectly spreadable. Taste and add a pinch of salt to balance the sweetness if needed.

Once the cakes are completely cool, use a large serrated knife to gently slice off the domed tops, ensuring the layers are flat and even.

Place the first layer of cake on a serving plate or cake stand. Spread approximately 1 cup of frosting across the top, smoothing it out to the edges.

Stack the second cake layer on top, then add another cup of frosting, spreading it evenly.

Position the final cake layer on top and cover the entire cake with a thin crumb coat of frosting. Chill the cake briefly to set the crumb coat, then apply a final, smooth layer of frosting over the top and sides.

Using the remaining buttercream, pipe a decorative border around the top edge of the cake for an elegant finish. Garnish with fresh orange slices, artfully arranged to complement the cake’s bright and vibrant flavor.

Store the cake in an airtight container at room temperature or in the refrigerator. For the best taste and texture, enjoy it within 4–5 days.