Preheat your oven to 350°F (175°C) and prepare a 9×5-inch loaf pan by greasing it with butter or lining it with parchment paper.

In a medium mixing bowl, whisk together the flour, baking powder, baking soda, salt, and poppy seeds.

In a large mixing bowl, cream the butter and sugar until fluffy, about 3-4 minutes.

Add the eggs one at a time, beating well after each addition, then mix in the vanilla.

Stir in the yogurt (or buttermilk), lemon juice, and zest until just combined.

Fold the dry ingredients into the wet mixture until just combined.

Pour the batter into the prepared loaf pan and smooth the top.

Bake for 50-60 minutes, checking for doneness with a toothpick.

Allow the loaf to cool in the pan for 10 minutes before transferring to a wire rack.

For the glaze, whisk together powdered sugar and lemon juice, then drizzle over the cooled loaf.