Begin by preheating the oven to 350 degrees F. Then spray the inside of a 9×5-inch loaf pan with baking spray. Set aside.

In a large bowl, whisk together the flour, sugar, baking powder, and salt. In a medium bowl, whisk together the eggs, milk, melted butter, sour cream, lemon zest, and vanilla extract.

Add the wet ingredients to the dry ingredients and mix until just combined. The batter may be slightly lumpy. Gently fold in the blueberries.

Pour the batter into the prepared loaf pan, spreading it in an even layer.

Bake for 65-70 minutes or until a toothpick inserted near the center comes out clean. (If needed, cover the bread with foil to prevent over browning.) Allow the bread to cool completely before slicing.