01 - Preheat oven to 375°F. Line a 12-cup muffin tin with paper liners or lightly grease.
02 - In a large bowl, whisk together flour, poppy seeds, baking powder, baking soda, and salt until evenly mixed.
03 - Rub lemon zest into sugar with your fingers to release oils. Whisk in eggs, Greek yogurt, melted butter, lemon juice, and vanilla extract until smooth.
04 - Add wet mixture to dry ingredients and gently fold until just combined without overmixing to maintain a tender crumb.
05 - Divide batter evenly among prepared muffin cups, filling each about three-quarters full.
06 - Bake for 18 to 20 minutes or until a toothpick inserted into the center comes out clean.
07 - Allow muffins to cool in the pan for 5 minutes, then transfer to a wire rack to cool completely.
08 - Whisk powdered sugar with lemon juice until smooth and pourable. Drizzle glaze over cooled muffins and allow it to set before serving.