Preheat oven to 400F
In a 12-inch cast-iron skillet, add olive oil over medium heat. Add carrots, celery, onion and rosemary, and cook until tender, about 10 to 12 minutes.
Add the arrowroot and stir until it coats the veggies and no flour is visible.
Add bone broth, milk, salt, pepper, and bring to a simmer. Turn the heat to low and simmer, stirring often, until very thick, 7 to 10 minutes and then remove from the heat.
Add the chicken and peas and stir to combine. Set aside while you shape your biscuits.
Shape the biscuit dough into rounds with your hands- divide the dough into seven equal sized biscuits.
Place the biscuits on top of the chicken and vegetable mixture.
Brush the tops of the biscuits with melted butter and sprinkle with coarse sea salt
Place the skillet on a sheet pan, and bake, uncovered, at 400F for 30 to 40 minutes, until biscuits are golden. Cool for 10 minutes to let the filling thicken slightly, then serve.
Enjoy!