Preheat your oven to 350°F and prepare two 8-inch round cake pans by greasing them thoroughly and lining the bottoms with parchment paper circles.

In a large mixing bowl, sift together the flour, sugar, cocoa powder, baking soda, baking powder, and salt, whisking to ensure even distribution.

In a separate bowl, whisk together the eggs, milk, oil, and vanilla extract until smooth and well combined.

Pour the wet ingredients into the dry ingredients and mix on medium speed just until combined, then slowly add the hot coffee while mixing on low speed.

Divide the batter evenly between the prepared pans and bake for 30-35 minutes, or until a toothpick inserted into the center comes out with just a few moist crumbs.

Allow the cakes to cool in their pans for 10 minutes before turning them out onto wire racks to cool completely.

While the cakes cool, prepare the blackberry filling by combining blackberries and sugar in a medium saucepan over medium heat, stirring occasionally.

Mix the cornstarch with water to create a slurry, then stir this into the simmering berry mixture and cook for 2-3 minutes until thickened.

Remove the filling from heat, stir in the lemon juice, then strain through a fine-mesh sieve to remove seeds, and allow to cool completely.

For the glaze, combine blackberries, sugar, water, and corn syrup in a saucepan and bring to a boil, then reduce heat and simmer for 8-10 minutes.

Strain the blackberry mixture through a fine-mesh sieve, then return the strained liquid to the pan and stir in the heavy cream, simmering for another 2-3 minutes.

Allow the glaze to cool to warm room temperature, stirring occasionally, until it reaches a honey-like consistency.

Place the first cake layer on your serving plate, spread the cooled blackberry filling evenly over the top, then carefully position the second layer on top.

Pour the warm blackberry glaze onto the center of the cake top and use an offset spatula to spread it toward the edges, allowing it to drip down the sides.

Immediately arrange fresh blackberries on top of the glazed surface and scatter edible silver decorative flowers around the berries.

Allow the glaze to set for at least 30 minutes at room temperature before slicing, or refrigerate for 15 minutes if serving sooner.