Preheat oven to 400 degrees F.
In a mixing bowl, whisk together dry ingredients: flour, baking powder, baking soda, salt, and poppyseeds.
In a separate mixing bowl, whisk together wet ingredients: sugar, vanilla, oil, milk, eggs, lemon zest and juice.
Gradually fold in the dry ingredients into the wet. Stir until just combined, being careful not to over-mix. The flour should be just combined, but batter should still be slightly lumpy.
Line 12 wells of a muffin pan with oven-safe liners or lightly coat with a non-stick spray. Evenly distribute batter between the 12 wells, about 2/3 of the way full.
Bake for 18 to 20 minutes, or until the muffins are lightly golden brown on top and a toothpick inserted into the center of the muffin comes out clean.
Let cool briefly before serving.