Creating the Blackberry Velvet Gothic Cake is a fun and rewarding process. Follow these steps to ensure success:

1. Preheat Oven: Preheat your oven to 350°F (175°C). Grease and flour three 9-inch round cake pans.
2. Mix Dry Ingredients: In a large bowl, whisk together flour, sugar, cocoa powder, baking soda, baking powder, and salt until well combined.
3. Combine Wet Ingredients: In another bowl, mix the milk, vegetable oil, eggs, and vanilla extract. Stir until smooth.
4. Combine Mixtures: Gradually add the wet mixture to the dry ingredients, stirring gently until just combined.
5. Add Boiling Water: Slowly mix in the boiling water and blackberry puree. The batter will be thin.
6. Divide Batter: Pour the batter evenly into the prepared pans.
7. Bake: Bake in the preheated oven for 40-50 minutes or until a toothpick inserted in the center comes out clean.
8. Cool: Allow the cakes to cool in their pans for 10 minutes before transferring them to wire racks to cool completely.
9. Prepare Frosting: In a medium bowl, beat the softened butter until creamy. Gradually add powdered sugar, blackberry puree, heavy cream, and vanilla extract. Beat until fluffy.
10. Assemble Cake: Once the cakes are completely cool, spread a layer of frosting between each cake layer, stacking them neatly.
11. Frost the Outside: Use the remaining frosting to cover the top and sides of the cake.
12. Decorate: Garnish with fresh blackberries, edible flowers, and dark chocolate shavings for an elegant finish.