Preheat your oven to 350°F (175°C). Prepare two 10-inch loaf pans by buttering and flouring them thoroughly.
In a large mixing bowl, cream together the sugar, salted butter, and lemon zest until light and fluffy. Beat in the eggs one at a time.
Pour in the vanilla extract and milk, mixing until just combined with your creamed mixture.
Sift together all-purpose flour and baking powder before gradually adding this dry mixture into your wet ingredients. Mix gently just until combined.
Gently fold in the floured blueberries using a spatula or wooden spoon.
Transfer your batter into prepared loaf pans evenly and bake for about 55-60 minutes until golden brown. Brush with lemon syrup and glaze with powdered sugar mixed with fresh lemon juice before serving.