Preheat the oven to 425˚F (220˚C). Line a large baking sheet with parchment paper.
Cut 6 tablespoons of the butter into ½-inch cubes and place them in the refrigerator to stay cold. Melt the remaining 1 tablespoon of butter in the microwave or on the stovetop (this will be for brushing the tops of the biscuits later).
In a liquid measuring cup or small bowl, whisk together the buttermilk and pumpkin puree.
In a food processor, combine the gluten-free flour, almond flour, coconut sugar, baking powder, salt and nutmeg. Process to combine. Scatter the cold butter over top. Pulse just until the butter is incorporated but you can still see pea-sized pieces.
Pour the buttermilk-pumpkin mixture over top then pulse until the mixture holds together when pressed—the mixture will still look a bit floury and you’ll still see little balls of butter, but the dough should stick together. If the dough is too dry, pulse in more buttermilk, 1 tablespoon at a time, until it sticks together.
Scrape the dough onto a piece of parchment paper and gently form it into a 1-inch-thick round (try to be as loving as you can—you want the dough to stick together, but you don’t want to compress it too much, otherwise the biscuits could turn tough).
Using a floured 2-inch biscuit cutter, press down to cut out the biscuits, cutting them as closely together as possible. Transfer the biscuits to the prepared baking sheet, spacing them at least 2 inches apart. Gather the remaining dough, pat it together, and cut out more biscuits. After that, discard any remaining scraps.
Brush the biscuits with the melted butter. Bake the biscuits until they’re golden brown, about 16-18 minutes. Transfer the biscuits to a rack and let cool slightly. Serve warm.