In a small bowl whisk together the all purpose flour, baking powder, and salt. Set aside the flour mixture.
2 cups (250 g) all-purpose flour, spooned and leveled, 1 tablespoon baking powder, ½ teaspoon salt
In a large bowl, whisk together the melted butter, granulated white sugar, eggs, sour cream, milk and vanilla extract.
½ cup (112 g) unsalted butter, melted, 1 cup (200 g) granulated white sugar, 2 eggs, at room temperature, ½ cup (122 g) sour cream, at room temperature, ½ cup (120 ml) whole milk, at room temperature, 1 teaspoon vanilla extract
Add the dry ingredients to the wet ingredients and whisk just until combined.
Add in the poppy seeds and lemon zest and gently fold them into the batter with a rubber spatula.
1 ½ tablespoon poppy seeds, 2 tablespoon (20 g) lemon zest
Cover the batter with plastic wrap and let the batter rest at room temperature for 1 hour.