Preheat the Oven: Preheat your oven to 350°F (175°C). Grease and flour a 9×5-inch loaf pan or line it with parchment paper for easy removal.
Prepare the Dry Ingredients: In a medium bowl, whisk together the flour, baking powder, baking soda, and salt. Set aside.
Cream the Butter and Sugar: In a large mixing bowl, cream the softened butter and sugar together until light and fluffy, about 2-3 minutes.
Add Eggs and Vanilla: Beat in the eggs, one at a time, ensuring each is fully incorporated before adding the next. Stir in the vanilla extract.
Combine Wet and Dry Ingredients: Gradually add the dry ingredients to the wet mixture, alternating with the milk. Start and end with the dry ingredients. Mix until just combined; avoid overmixing.
Fold in Blueberries: Gently fold the blueberries into the batter. If using frozen blueberries, toss them in a little flour to prevent them from sinking.
Prepare the Cream Cheese Filling: In a separate bowl, beat the cream cheese, sugar, egg, and vanilla until smooth and creamy.
Assemble the Bread: Pour half of the bread batter into the prepared loaf pan. Spread the cream cheese filling evenly over the batter. Top with the remaining batter, spreading it out evenly.
Bake: Bake in the preheated oven for 50-60 minutes or until a toothpick inserted into the center comes out clean. If the top begins to brown too quickly, cover it loosely with aluminum foil during the last 15 minutes of baking.
Cool and Serve: Allow the bread to cool in the pan for about 10 minutes, then transfer it to a wire rack to cool completely. Once cooled, slice and enjoy!
