01 - Preheat oven to 350°F. Grease and line a 9x5 inch loaf pan with parchment paper.
02 - In a small bowl, mix flour, brown sugar, cinnamon, and salt. Add cold butter and blend until mixture is crumbly. Refrigerate until ready to use.
03 - In a medium bowl, whisk together flour, baking powder, baking soda, and salt; set aside.
04 - In a large bowl, beat butter and sugar until light and fluffy. Add eggs one at a time, beating well after each.
05 - Mix in milk, lemon juice, lemon zest, and vanilla extract until combined.
06 - Gradually add dry ingredients to wet ingredients, mixing just until combined. Do not overmix.
07 - Gently fold in blueberries with a spatula.
08 - Pour batter into prepared loaf pan and smooth the top. Sprinkle streusel evenly over the batter.
09 - Bake for 50–60 minutes, or until a toothpick inserted into the center comes out clean.
10 - Cool in the pan for 10 minutes, then lift bread out and transfer to a wire rack to cool completely before slicing.