01 - Preheat the oven to 375°F and line a 12-cup muffin tin with paper liners or grease it lightly.
02 - Whisk flour, poppy seeds, baking powder, baking soda, and salt together in a large bowl.
03 - In a separate bowl, rub granulated sugar and lemon zest together with your fingers to release the oils.
04 - Add eggs, Greek yogurt, vegetable oil, lemon juice, and vanilla extract to the sugar mixture and whisk until smooth.
05 - Pour the wet ingredients into the dry ingredients and stir gently until just combined; avoid overmixing.
06 - Divide batter evenly among muffin cups, filling each roughly three-quarters full.
07 - Bake for 18 to 20 minutes, or until a toothpick inserted into the center comes out clean.
08 - Allow muffins to cool in the pan for 5 minutes, then transfer to a wire rack to cool completely.