Preheat oven to 350 degrees. In a microwave or small pot, melt butter and let it cool slightly. Separate 2 tsp. each of sugar and poppy seeds and set aside for topping. Zest and juice lemon. In a medium mixing bowl, whisk together flour, baking powder, baking soda, and salt. In another medium mixing bowl, whisk together sugar, eggs, 2 Tbsp. lemon juice, ¾ tsp. lemon zest, and milk.