01 -
Start by cooking 1 1/2 cups blackberries with a bit of sugar and some water in a small pot over medium heat for 8 to 10 minutes until thick. Mash gently and press through a fine sieve to get rid of seeds. Let it chill well. Set aside half a cup for the batter and a third cup for the frosting.
02 -
Heat your oven to 350°F. Grease two 8-inch cake pans, line their bottoms with parchment, and dust flour on top so the cake doesn’t stick.
03 -
Whisk flour, baking powder, baking soda, and salt together in a bowl.
04 -
Beat softened butter with sugar in a mixer at medium speed. Keep going till it’s fluffy and light, about 3 to 4 minutes.
05 -
Add eggs one by one, making sure each is mixed in well. Then stir in vanilla and lemon zest if you’re using it.
06 -
In another bowl, whisk together the buttermilk and the blackberry sauce you saved earlier (half a cup).
07 -
Slowly fold the dry stuff into the wet mixture just until it’s mixed. Then stir in the rest of the blackberry puree.
08 -
Pour the batter evenly into your pans. Bake for 30 to 45 minutes or until a toothpick comes out clean. Cool the cakes in the pans for 10 minutes before moving them onto wire racks to cool off completely.
09 -
Mix butter and cream cheese until smooth and fluffy, around 2 minutes. Slowly add powdered sugar, the remaining blackberry sauce, vanilla, and a pinch of salt. Beat until creamy and light for about 3 minutes. Chill if it feels too soft.
10 -
Put some frosting between the cake layers and cover the outside too. Top with fresh blackberries for a pretty finish.