Preheat the Oven: Preheat your oven to 425°F (220°C) and line a baking sheet with parchment paper.
Mix Dry Ingredients: In a large mixing bowl, whisk together the flour, baking powder, baking soda, and salt until well combined.
Cut in Butter: Add the cold, cubed butter to the flour mixture. Using a pastry cutter or your fingertips, quickly work the butter into the flour until the mixture resembles coarse crumbs.
Add Buttermilk: Make a well in the center of the flour mixture. Pour in the buttermilk and gently mix until just combined. Avoid over-mixing.
Incorporate Herbs and Cheese: Fold in the chopped fresh herbs and shredded cheese (if using) until evenly distributed throughout the dough.
Shape the Dough: Turn the dough out onto a lightly floured surface. Pat it down into a rectangle about 1 inch thick. Fold the dough in half, then gently pat it down again into a rectangle. Repeat this folding process 2-3 times to create flaky layers.
Cut the Biscuits: Using a floured biscuit cutter, cut out biscuits from the dough and place them onto the prepared baking sheet, leaving a little space between each one.
Egg Wash: Brush the tops of the biscuits with the beaten egg to give them a beautiful golden color when baked.
Bake: Place the baking sheet in the preheated oven and bake for 12-15 minutes, or until the biscuits are puffed and golden brown on top.
Serve: Remove from the oven and let cool slightly before serving warm. These biscuits are perfect on their own or with butter, jam, or your favorite spread!
Notes
Feel free to mix and match herbs according to your preference.