Preheat oven to 400 degrees. Line a baking sheet with, silicone mat, foil, or parchment paper.
In the bowl of a stand mixer*, using the paddle attachment on low speed, mix together flour, brown sugar, baking powder, and salt. Once combined, add the butter and mix on medium speed until the mixture resembles coarse crumbs.
In a separate bowl, whisk together heavy cream, sour cream, egg, and vanilla extract. Slowly add the wet ingredients into the dry ingredients, and mix until just combined.
Stir in the peaches, and mix until just combined.
On a well-floured surface, turn out the scone dough and pat into a small disk that's about a 1/2" thick. Cut into 6-8 slices, and transfer to the baking sheet. Brush each scone with just a bit of heavy cream.
Bake for 15-18 minutes, or just until golden brown. Allow to cool.
To make the Maple Glaze:
Whisk together powdered sugar, vanilla extract, and 1 Tbsp of heavy cream. If the glaze is too thick, continue adding in heavy cream, one 1 Tbsp at a time, until it has reached the desired consistency. Pour over warm scones and enjoy!