Preheat oven to 425°F.
Sift together flour, sugar, baking powder, salt, baking soda in large mixing bowl.
Add cold butter cubes to flour mixture. Blend in butter with pastry cutter or fingers until it resembles coarse meal.
Add buttermilk and mix until dough just begins to come together.
Place dough on well-floured surface and gently knead. Pat out dough to ½” thick disc. Make sure hands and surface stay floured, as this will be a soft dough.
Punch out 8 shortcakes with a 3” round cutter. This will be done in two batches.
Place shortcakes on baking sheet with silicone baking mat.
Brush with whole milk and sprinkle with turbinado sugar or sanding sugar.
Bake for 12-15 minutes. Let cool to room temperature.
Once cool, split open shortcake and top with grilled peach slices and whipped cream. Enjoy! Shortcakes are best eaten the day of baking.