In a mixing bowl,whisk together the cake flour, all-purpose flour, sugar, baking powder and baking soda. Now, add eggs, oil, lemon juice, or emulsion oil and lemon zest. Mix until everything is smooth
Add sour cream and mix until just combined. Don't over-mix!
Pour this batter in two round greased/floured cake pans (Dimension: 8x2). Bake at 350 degrees for 40 minutes or until an inserted toothpick comes out clean.
While the cake is baking and then cooling down, make lemon curd and frosting.
Place one cake on a cake stand and top it off with a thin layer of frosting and lemon curd. Place the other cake on top of all this. Press your cake down with your hands (some of the frosting and curd will come out from the sides but don't worry about it!)
Now, use a spatula to frost the entire cake roughly with frosting.
Finally, pour some lemon curd on top of the cake and place some berries here.
Keep this cake refrigerated until you are ready to serve.
Note: Prior to serving, if any frosting or curd has come out from the sides along the center of the cake, just run a spatula around the cake again. And you are done!