Preheat the oven to 425 degrees F, and line a muffin pan with papers.
Place the flour, sugar, poppy seeds, baking powder, salt, and lemon zest in a large mixing bowl, and whisk to combine.
Melt the butter in a large liquid measuring cup, and whisk together with the Greek yogurt, milk, eggs, lemon juice, and lemon extract.
Pour the liquid ingredients into the dry, and fold together until just barely combined (batter will be very thick).
Divide the batter equally between all 12 wells of the muffin pan.
Bake the muffins for 5 minutes at 425 degrees F, then turn the oven temperature down to 350 degrees F and continue to bake for 14 to 18 minutes, or until a toothpick inserted in the thickest part of a muffin comes out clean or with a few moist crumbs.
Drizzle with lemon glaze and serve.