Preheat oven to 325 degrees F (165 degrees C). Grease a 9x13-inch baking dish.
Beat white sugar and shortening together in a bowl using an electric mixer until creamy; add eggs and mix well. Mix cinnamon, cloves, and vanilla extract into creamed butter mixture.
Whisk buttermilk and baking soda together in a separate bowl; stir into creamed butter mixture until thoroughly mixed. Slowly stir flour into butter-buttermilk mixture until batter is smooth; fold in blackberries. Pour batter into the prepared baking dish.
Bake in the preheated oven until a toothpick inserted in the center of the cake comes out clean, about 40 minutes. Cool in the pan for 10 minutes before removing to a serving plate.
Combine brown sugar, evaporated milk, and butter in a saucepan; cook and stir mixture over medium heat until a small amount of brown sugar mixture dropped into cold water forms a soft ball. Remove saucepan from heat and stir in vanilla extract. Beat by hand until icing is thick. Spread icing quickly over top and sides of cake.
All done! Now take a photo, rate it, and share your accomplishments!