First, brown the butter: In a small pan, heat the butter. After the butter melts and foams, it will begin to turn golden brown with a nutty aroma. Stir frequently, watching carefully until it just browns. Pour the browned butter with any crispy bits into a parchment-lined bowl and refrigerate until solid, at least an hour.
Preheat the oven to 450°F.
Toss the peaches with tapioca starch and brown sugar in a medium skillet. Heat on the stove, stirring until just warm and beginning to bubble, 3-5 minutes. If using a cast iron skillet, you can bake it right in the skillet, otherwise, transfer it to an 9-inch round or 9x9-inch square baking dish.
In a medium bowl, whisk together the chestnut flour, oat flour, sweet rice flour, tapioca starch, xanthan gum, sugar, baking powder, soda, and salt.
When the butter is chilled, cut it into ¼-inch pieces, add it to the flour and, working quickly, use your hands or a pastry knife to combine until the largest pieces of butter are no bigger than a pea.
Add the buttermilk and stir with a fork to completely combine.
Divide the biscuit dough into six pieces. Slightly flatten them into round disks and plop them on top of warm peaches.
Bake for 20-24 minutes, until the biscuits are golden brown on top, kissed with a few dark spots.
Serve warm with vanilla ice cream.
Notes
*I grind my own oat flour by pulsing gluten-free oats in the blender or food processor until fine, then sifting out any large pieces.**If you don't have time to chill the brown butter, you can skip the brown butter step and just use regular butter - the biscuits will still be tasty! If not browning the butter, use only 3 tablespoons of butter!
This nutritional information has been automatically calculated, and as such, may be incomplete or inaccurate. Please reference the specific ingredients you use for the most accurate nutritional information.