Preheat the Oven: Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper.

Make the “Buttermilk”: In a small bowl, combine the heavy cream and apple cider vinegar. Stir and let sit for 5-10 minutes. This mixture will curdle slightly, resembling buttermilk.

Mix the Dry Ingredients: In a large bowl, whisk together the almond flour, coconut flour, baking powder, baking soda, and salt.

Cut in the Butter: Add the cold, cubed butter to the dry ingredients. Use a pastry cutter or your fingers to cut the butter into the flour until the mixture resembles coarse crumbs.

Combine Wet Ingredients: In a separate bowl, whisk the eggs and add the “buttermilk” mixture. Pour this into the dry ingredients and gently stir until a dough forms. If adding cheese or other mix-ins, fold them in at this stage.

Form the Biscuits: Turn the dough out onto a lightly floured surface (use almond flour to prevent sticking). Pat the dough into a rectangle about 1 inch thick. Use a biscuit cutter or a glass to cut out biscuits, gently reshaping the dough scraps as needed. Place the biscuits on the prepared baking sheet.

Bake: Bake the biscuits in the preheated oven for 12-15 minutes, or until the tops are golden brown and the biscuits are cooked through.

Cool and Serve: Let the biscuits cool slightly on the baking sheet before transferring them to a wire rack. Serve warm with butter or your favorite low-carb topping.