Mix dry ingredients: In a large bowl, combine 200g cake flour, 4g baking powder, and 40g sugar. Stir well with chopsticks to ensure the dry ingredients are evenly distributed.

Add wet ingredients: Add 105g heavy cream and 1 egg to the dry ingredients. Use a spatula to gently fold the mixture until no dry flour remains, forming a moist dough. Be careful not to overmix to avoid developing gluten.

Add corn oil: Pour in 20g corn oil and continue mixing with the spatula until the oil is fully incorporated, making the dough more moist.

Add crushed Oreos: Add 70g crushed Oreos to the dough and mix evenly using your hands or the spatula, ensuring the Oreos are evenly distributed throughout the dough.

Dough handling and refrigeration: Sprinkle a thin layer of flour on the countertop. Place the dough on the floured surface, then dust the dough with more flour. Use a rolling pin to gently flatten the dough. Sprinkle some more flour, cut the flattened dough into 4 pieces, stack them on top of each other, and flatten again using the rolling pin. Repeat the process of dusting, cutting, stacking, and flattening one more time. Afterward, wrap the dough in plastic wrap and refrigerate for 30 minutes to relax and firm up the dough for easier handling.

Shaping and egg wash: Remove the dough from the refrigerator and roll it out on a floured surface to a thickness of 1cm. Use a round cutter or any preferred shape to cut the dough into scone shapes. Place the scone dough on a baking tray and brush the tops with a thin layer of egg yolk.

Bake the scones: Bake in the preheated oven for 25 minutes. Keep an eye on the scones as they bake. When the tops turn golden brown and the scones feel slightly firm when pressed, they are done.

Cool and enjoy: Remove the scones from the oven and allow them to cool on a wire rack. They taste best when cooled, soft and fluffy with the sweet aroma of Oreos. Enjoy!