Preheat the oven to 375F (190C). Line a 12-cavity muffin pan with paper liners.
In a medium bowl whisk together flour with baking powder, poppy seeds and salt.
In a large bowl add sugar and lemon zest. Mix to release oils from the zest and the sugar becomes pale yellow.
Add eggs and mix to combine.
Add lemon juice and vanilla extract and mix to combine.
Gradually incorporate the oil.
Incorporate the flour mixture.
Alternate with the buttermilk.
Don’t overmix the batter.
Divide the batter equally into muffin cups.
Bake for about 20-25 minutes until lightly golden and a toothpick inserted into the center comes out clean.
Cool muffins on a wire rack.