Dice or grate the cold butter into small pieces and add to the flour mixture. Cut the butter into the flour with a pastry cutter, a fork, or even your hands until the pieces of butter are evenly distributed. The flour mixture will be coarse and sand-like.

Add sourdough starter and buttermilk, stirring until just combined. The dough will be lumpy. Cover the dough and keep it in the refrigerator while you prepare the filling.

Start the filling by adding butter, garlic, onion, potatoes, and carrots to a large cast iron skillet on medium-low heat. Sauté for 10 minutes until the vegetables start to soften.

Sprinkle the flour over the sautéed vegetables, then stir and cook for a few minutes until the flour is mixed in well.

Pour in the bone broth and add parsley, salt, pepper, garlic powder, and onion powder. Mix well, cover with a lid, and cook for 10 minutes.

Stir in peas, pre-cooked chicken, and heavy cream, then transfer the filling to a greased 9x13 baking dish.

Preheat oven to 400°F (200°C).

Roll biscuit dough onto a lightly floured surface and cut out biscuits (approx. 12). Place on top of the pot pie filling, side to side.

Bake for 10-15 minutes or until the biscuits are golden and the filling is bubbling.

Remove from the oven and cool for several minutes before serving.