Preheat the oven to 350°F (175°C). Line a 9x5-inch loaf pan with parchment paper, leaving overhang for easy lifting. Lightly grease the sides.

In a large bowl, whisk together the flour, baking powder, baking soda, salt, and poppyseeds. Set aside.

In a separate bowl, add the sugar and lemon zest. Use your fingers to rub the zest into the sugar until it smells very lemony. This releases the oils and boosts flavor.

Whisk the eggs into the lemon sugar until smooth. Add the oil, Greek yogurt, lemon juice, and vanilla. Whisk until fully combined and creamy.

Pour the wet ingredients into the dry ingredients. Use a spatula to fold gently until no streaks of flour remain. Avoid overmixing.

Transfer the batter to the prepared loaf pan. Smooth the top with a spatula.

Bake for 45–55 minutes, or until the top is golden and a toothpick inserted in the center comes out mostly clean with a few moist crumbs. If the top browns too fast, tent loosely with foil during the last 10 minutes.

Cool in the pan for 10–15 minutes. Lift out using the parchment and place on a wire rack to cool to barely warm.

Make the glaze by whisking powdered sugar with 2 tablespoons lemon juice. Add more juice (or a splash of milk) until it’s thick but pourable.

Drizzle the glaze over the warm loaf. Let it set for at least 15 minutes before slicing.