Preheat oven to 350° F degrees.
Grease, flour & line a 9-inch round baking dish with parchment paper.
In a large mixing bowl whisk together the butter, sugar, eggs, ricotta, vanilla & lemon juice until well combined.
Sift in the flour, baking powder, salt & lemon zest. Mix until batter comes together. Fold in the fresh raspberries, reserving a handful for the top.
Transfer batter to prepared baking dish. Using an offset spatula, smooth the top to flatten. Sprinkle with reserved raspberries.
Bake for 45 to 50 minutes, until the centre of the cake bounces back to touch. Let cool to room temperature before slicing & serving.