Prep the pan and oven: Heat oven to 350°F (175°C). Line a 9x5-inch loaf pan with parchment, letting it overhang for easy lifting. Lightly grease the parchment and sides.

Mix dry ingredients: In a medium bowl, whisk 1 1/2 cups all-purpose flour, 2 teaspoons baking powder, and 1/2 teaspoon salt. Set aside.

Whisk wet ingredients: In a large bowl, whisk 3/4 cup granulated sugar with the zest of 2 lemons until fragrant. Add 2 large eggs and whisk until slightly thickened and pale, about 30 seconds. Whisk in 1/2 cup plain Greek yogurt, 1/3 cup neutral oil, 2 tablespoons melted cooled butter (optional), 2 tablespoons fresh lemon juice, and 1 teaspoon vanilla until smooth.

Prepare the blueberries: Toss 1 cup blueberries with 1 teaspoon flour to coat. This helps suspend them in the batter.

Combine batter: Add the dry ingredients to the wet. Stir gently with a spatula until just combined; a few small lumps are fine. Fold in the blueberries, reserving a small handful to scatter on top.

Fill and smooth: Scrape the batter into the prepared pan and smooth the top. Scatter the reserved berries over the surface and lightly press them in.

Bake: Bake for 50–60 minutes, until the top is golden and a skewer inserted in the center comes out with moist crumbs but no wet batter. If browning too fast, tent loosely with foil for the last 10 minutes.

Cool: Let the loaf cool in the pan on a rack for 15 minutes. Lift it out using the parchment and cool completely before glazing.

Glaze: In a small bowl, whisk 3/4 cup powdered sugar with 1–2 tablespoons fresh lemon juice until smooth and pourable. Drizzle over the cooled loaf, letting it drip down the sides. Allow 15 minutes to set before slicing.

Slice and serve: Use a serrated knife for neat slices. Serve plain or with a dollop of yogurt or whipped cream if you like.