Prepare Dry Ingredients: Sift together the all-purpose flour, baking powder, lemon zest, and salt. Set aside.
Cream Butter and Sugar: In a mixing bowl, cream the unsalted butter and granulated sugar until light and fluffy.
Add Eggs and Vanilla: Beat in the eggs one at a time, then add the vanilla extract and mix well.
Combine Wet and Dry Ingredients: Alternately add the dry ingredients and lemon juice to the butter mixture, beginning and ending with the dry ingredients. Mix until just combined.
Add Yogurt: Fold in the Bulla Australian Style Blueberry Yoghurt gently into the batter.
Bake the Cake: Pour the batter into a greased loaf pan and bake at 175°C (350°F) for about 50-60 minutes or until a toothpick inserted comes out clean.
Prepare Lemon Syrup: While the cake is baking, mix lemon juice and icing sugar until sugar dissolves to make the lemon syrup.
Brush Cake with Lemon Syrup: Once the cake is out of the oven, brush the lemon syrup over the warm cake to add moisture and flavor.
Prepare Yogurt Icing: Mix icing sugar and Bulla Australian Style Yoghurt until smooth to make the yogurt icing.
Decorate and Serve: Optionally, top the cooled cake with yogurt icing and fresh blueberries for a fancy presentation.