01 - Preheat oven to 350°F (175°C). Prepare a 9x5-inch loaf pan by greasing and lining it with parchment paper.
02 - In a large mixing bowl, whisk together flour, baking powder, baking soda, and salt until thoroughly combined.
03 - In a separate bowl, whisk eggs, milk, yogurt (or sour cream), melted butter, granulated sugar, maple syrup (if using), vanilla extract, lemon zest, and lemon juice until smooth.
04 - Pour the wet ingredients into the dry ingredients. Stir gently until just incorporated; avoid overmixing.
05 - Gently toss blueberries with 1 tablespoon of flour. Carefully fold the floured blueberries into the batter.
06 - Spoon the batter into the prepared loaf pan, smoothing the top. Bake for 45–55 minutes, or until a toothpick inserted into the center emerges clean. If the top begins to brown too rapidly, loosely tent with aluminum foil after 30 minutes.
07 - Allow the bread to cool in the pan for 10 minutes before inverting it onto a wire rack to cool completely.
08 - Whisk powdered sugar and lemon juice until a smooth glaze forms. Drizzle over the cooled bread before serving.