Preparation Methods
1. Preheat Your Oven: Set 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 of your loaf.
2. Prepare the Dry Ingredients: In a medium bowl, whisk together the flour, baking powder, baking soda, and salt. Set this bowl aside.
3. Cream the Butter and Cream Cheese: In a large mixing bowl, beat the softened butter and cream cheese together until light and fluffy. This should take about 3 minutes. The cream cheese adds richness and moisture, making the loaf dense yet soft.
4. Add the Sugar and Eggs: Gradually add the sugar and beat until smooth. Add the eggs one at a time, beating well after each addition. Stir in the vanilla extract.
5. Mix the Wet and Dry Ingredients: Add the dry ingredients to the wet ingredients in batches, alternating with the sour cream or yogurt. Mix until just combined—do not overmix, or your loaf may become dense.
6. Add the Blueberries: Gently fold in the blueberries with a spatula. Be careful not to crush them, as you want to keep those beautiful pockets of juicy berries intact.
7. Prepare the Cream Cheese Filling: In a separate bowl, beat together the cream cheese, powdered sugar, and vanilla extract until smooth and creamy.
8. Layer the Ingredients in the Pan: Pour half of the batter into the prepared loaf pan. Next, drop spoonfuls of the cream cheese filling over the batter and gently spread it into an even layer. Top with the remaining batter and smooth it out. You can use a butter knife to gently swirl the cream cheese filling into the batter for a marbled effect.
9. Bake the Loaf: Place the loaf pan in the oven and bake for 60–70 minutes, or until a toothpick inserted into the center comes out clean (though it may come out with a few crumbs). If the top starts to brown too quickly, you can cover it loosely with aluminum foil for the last 15 minutes of baking.
10. Cool and Serve: Allow the loaf to cool in the pan for 10 minutes before transferring it to a wire rack to cool completely. This step helps the loaf set and makes it easier to slice.
