Prepare the carrot dough. Add sugar and sunflower oil to a deep bowl and beat with a mixer at maximum speed for about 1-2 minutes. Add one egg at a time to the mixture and beat thoroughly.
In a separate bowl, sift the flour together with the baking powder. Add the soda, nutmeg and cinnamon. Mix everything carefully and thoroughly.
Mix the egg and dry mixtures. Pour in half a glass of chopped nuts and stir. The dough should be viscous.
Grate the carrots on a fine grater. Add them to the dough and mix with folding movements, moving the spatula or spoon from the bottom up. The carrots will make the dough more liquid, but it should still remain viscous.
Start baking the crust. It is best to bake the dough in parts, then it will bake evenly and the crusts will not need to be cut. Weigh all the dough and divide into 3 equal parts. Pour the first portion into the pan and bake for 15-20 minutes. You can check the readiness with a toothpick. If you pierce the crust with it, it may come out with crumbs, but there should be no traces of wet dough.
Remove the cake from the oven and let it sit for a couple of minutes. Then carefully run a knife between the sides of the pan and the edge of the cake. Remove the cake from the pan and let it cool.
Prepare the remaining cakes. Wash the pan, wipe dry and pour in the next portion of dough. Bake the remaining three cakes in the same way. Cool them completely.
Prepare the cream. Using a mixer at maximum speed, beat the butter with the powdered sugar for about 3 minutes, until the mixture becomes smooth and airy. Add the cheese and beat the cream for 3-5 minutes.
Start assembling the cake. Spread the cooled layers with cream, smooth them out and assemble the cake. Spread the remaining cream on the sides of the cake. Decorate the top of the cake with berries and put the cake in the refrigerator for a few hours.