Preheat your oven to 350°F (175°C) and prepare two 8-inch round cake pans by greasing them and lining the bottoms with parchment paper.

In a large mixing bowl, combine granulated sugar and lemon zest, then add flour, baking soda, baking powder, and salt, mixing well.

Gradually incorporate softened unsalted butter and Greek yogurt, then mix in the eggs and vanilla extract until smooth. Fold in the blackberries.

Divide the batter between the pans and bake for approximately 30 minutes, rotating halfway through.

While the cakes cool, prepare the blackberry layer by mixing blackberries, sugar, and lemon juice, letting it sit for about 15 minutes.

For the lemon curd mascarpone, whisk together egg yolks, sugar, and salt over a double boiler until thickened. Stir in lemon zest and juice, then fold in mascarpone.

Whip heavy cream until soft peaks form, then fold it into the lemon curd mixture to create the frosting.

Once cakes are cooled, slice each layer in half and layer them with mascarpone frosting and macerated blackberries.

Assemble the cake, cover it, and chill in the fridge for 1-2 hours before serving.