Preheat oven to 375°F. Line a large baking sheet with parchment paper.
In a large bowl combine flour, brown sugar, baking powder, nutmeg or cardamom, and salt and whisk well to combine. Be sure brown sugar isn't clumped.
Cut in the cold butter cubes with a pastry cutter or two forks, until the mixture resembles coarse meal. Set aside.
In a small bowl whisk together the egg, sour cream or yogurt, heavy cream and extracts. Slowly stream into the flour mixture and combine just until the ingredients are wet and form a sticky dough.
Gently fold in the diced peaches.
Turn the dough out onto a floured work surface and shape into an 8-inch circle about 1 1/2-inch thick. Flour and knead as needed to shape the dough - it will be very sticky.
Cut the dough into 8 equal wedges and transfer them to the prepared sheet, placing them at least 1 1/2-inches apart.
Bake for 20 to 25 minutes, or until centers are set and the bottoms are lightly golden.
Allow scones to cool for 10 minutes on the baking sheet then transfer to a cooling rack.