Preheat oven to 350º F. Spray two 6-inch cake pans with non-stick cooking spray and line with parchment paper circles.
Purée the berries in a blender or small food processor.
Strain puréed berries through a sieve. Reserve 2/3 cup berry puree. Set aside remaining puree for syrup.
In a medium bowl, sift together flour, baking powder, baking soda, and salt. Set aside.
In a large bowl, beat 1 1/4 cups (8.75 ounces) sugar, oil, eggs and vanilla extract with an electric mixer on medium speed, until light and fluffy, about 1 minute.
Add flour in two additions, alternating with buttermilk, beating at medium speed just until combined.
Stir in the reserved 2/3 cup berry purée.
Pour batter evenly into the prepared cake pans. Bake until a toothpick inserted into center of cakes comes out clean, about 30-35 minutes.
Cool cakes in pans for 10 minutes. Remove cakes from pans and continue cooling on wire racks.
Meanwhile, make berry syrup. In a small saucepan, heat the remaining berry purée, remaining 1/4 cup sugar (1.75 ounces) and 1/4 cup water over medium-low heat. Stir together and bring to a boil. Cook until sugar is dissolved. Set aside to cool.
Split each cake layer into two and brush with berry syrup. Fill and frost cake with Silky Cream Cheese Frosting.
Silky Cream Cheese Frosting
In a large bowl, beat butter and cream cheese with an electric mixer at medium speed, until smooth.
Add vanilla extract and salt and beat until combined.
Gradually add powdered sugar and beat at medium speed until combined.
Add heavy cream and beat at low speed until smooth and creamy.
Add gel food color with a toothpick, a little at a time, until desired shade is reached. Beat at low speed until well blended.
Finishing Touches
Garnish top of cake with fresh berries. Brush a few of the berries with edible gold luster dust. Garnish with fresh flowers immediately before serving.