Sift the flour into a large mixing bowl. Then add in the sugar, poppy seeds, lemon zest, baking powder, baking soda, and salt. Gently whisk to combine.
2 cups All Purpose Flour, spooned and levled, 2 1/2 Tbsp. poppy seeds, 1/3 cup sugar, 2 Tbsp. lemon zest, or more as desired, 1 Tbsp. baking powder, 1/2 tsp. baking soda, 1 tsp. kosher salt
Add the cold, cubed butter pieces and using a pastry cutter, cut the butter into the flour until butter is the size of peas. (I sometimes use my hands for this, but since heat from fingers and hands warm up the butter, if you use this method be sure to freeze or refrigerate the scones for just 15-30 minutes prior to baking).
6 Tbsp. cold, unsalted butter, cut into small cubes
Whisk together the Greek yogurt, cold heavy cream, and lemon juice in a separate bowl.
1/2 cup plain, full fat Greek Yogurt, 1/2 cup heavy cream, cold + 2 Tbsp, divided, 2 Tbsp. fresh lemon juice
Add the Greek yogurt mixture into the dry ingredients and stir just until it begins to come together.
Transfer dough to a lightly floured surface and gently begin to knead the dough to bring it together. Be sure to handle the dough lightly, as you don't want to over-work this dough. Make sure to use a little flour on your hands and on your work surface so the dough does not stick. Fold the dough in half over itself and use your hands to gently flatten layers together.
Shape the dough into a large circle ~1 inch thick. Using a knife or bench scraper, cut in half long ways, and then cut again crossways, and make each section into triangles. It will make 8 scones.
Transfer the wedges to a baking sheet lined with parchment paper and place about 2" apart.
Place in the freezer for 15-30 minutes or until dough is chilled.
Preheat the oven to 400°F.
Brush lightly with heavy cream and sprinkle with coarse sugar on top. Bake for ~16-18 minutes or until tops are lightly browned. Careful not over bake, scones will become dry.
Remove from oven and let cool.