01 - Preheat the oven to 400°F and line a baking sheet with parchment paper.
02 - In a large bowl, whisk together flour, sugar, poppy seeds, baking powder, baking soda, and salt.
03 - Add cold butter and lemon zest to the dry mixture. Use a pastry cutter or fingertips to blend until mixture resembles coarse crumbs.
04 - In a separate bowl, whisk heavy cream, egg, vanilla extract, and lemon juice until combined.
05 - Pour wet ingredients into dry ingredients and gently stir with a fork until just combined; avoid overmixing.
06 - Turn dough onto a floured surface. Pat into a 1-inch thick round, cut into 8 wedges, and arrange on prepared baking sheet.
07 - Lightly brush the tops of scones with additional heavy cream.
08 - Bake for 16 to 18 minutes until golden brown. Allow to cool slightly on a wire rack.
09 - Whisk powdered sugar with lemon juice until a drizzle consistency is reached and drizzle over warm scones.