Preheat your oven: Set your oven to 350°F (175°C) and grease a bundt pan or loaf pan with butter and flour.
Mix Butter and Sugar: In a large bowl, cream together the softened butter and granulated sugar until light and fluffy. This will take about 3-5 minutes.
Add Eggs: Beat in the eggs one at a time, ensuring each is fully incorporated before adding the next.
Combine Dry Ingredients: In another bowl, whisk together the flour, baking powder, baking soda, and salt.
Mix Together: Gradually add the dry mixture to the creamed mixture, alternating with the sour cream. Mix until just combined.
Add Zest and Juice: Gently fold in the lemon zest and lemon juice for that unmistakable citrus flavor.
Toss Blueberries: Lightly coat the blueberries in a bit of flour (this prevents them from sinking) and fold them into the batter.
Bake: Pour the batter into your prepared pan and bake for about 55-60 minutes, or until a toothpick comes out clean when inserted into the center.
Cool and Serve: Once baked, allow the cake to cool in the pan for 10-15 minutes before inverting it onto a wire rack to cool completely.