Preheat oven to 350 and line a round 8-inch baking pan with parchment paper and set aside.
Add salt in a medium-sized mixing bowl. Whisk until well combined.
In a large mixing bowl with the paddle attached, add softened butter and goat cheese to the bowl and mix for one minute to combine
Add sugar and lemon zest. Beat with the butter for 2 minutes until pale and creamy. Scraping down the sides as needed.
Add eggs one at a time. Scrape down the sides as needed.
Pour in milk, oil, lemon juice, and vanilla and combine well
Add the dry flour mixture and beat until just combined
Scrape down the sides and add the remaining flour. Beat until incorporated, ensuring not to over-beat, just until the flour has combined.
Pour batter into the lined pan and smooth out the top with a spatula or by banging the pan hard on the counter until the batter settles
Dot the blackberries along the top of the cake, pressing about halfway into the batter
Bake for 40-45 minutes, or until a toothpick inserted into the middle comes out clean and lightly golden all over.
Let cool for 15 minutes, then lift out of the pan for serving
Finish with a sprinkling of super fine caster sugar or powdered sugar if desired.
