Preheat the oven to 350°F (175°C). Grease and flour a 9x5-inch loaf pan.
In a large bowl, cream together the butter, sugar, and cream cheese until smooth and fluffy.
Add eggs one at a time, beating well after each addition. Mix in vanilla extract.
In another bowl, whisk together the flour, baking powder, and salt.
Gradually add the dry ingredients to the wet mixture, alternating with milk. Mix just until combined.
Toss the blueberries with 1 tablespoon of flour and gently fold them into the batter.
Pour the batter into the prepared loaf pan and spread evenly.
Bake for 50–60 minutes, or until a toothpick inserted in the center comes out clean.
Allow the bread to cool in the pan for 10 minutes before transferring to a wire rack to cool completely.