Preheat the oven 450 degrees F.
Add the dry ingredients to a large bowl and stir to combine. Cut the cold butter into chunks and cut it into the flour until the dough resembles coarse crumbs. Pour in the buttermilk and mix until combined.
Turn the dough onto a floured board and gently roll it out until it's about 1/2-inch thick. Using a round cutter, cut the dough into 12 biscuits and arrange them on a cookie sheet. Bake until the biscuits are golden brown, about 10 to 12 minutes.
In a medium-sized pot, add the chicken pieces and enough water to cover. Boil over high heat until the chicken is cooked through, then remove them from the water to a plate.
In a large pot, over medium heat, add the melted margarine or butter along with the celery, carrots, onions, green peppers, poultry seasoning, and black pepper. Saute until the vegetables become soft. Add the flour and stir continuously to prepare a roux.
To a large saucepan, add the 4 cups water and the bouillon cubes. Bring to a boil over medium heat. Once the mixture comes to a boil, turn off the heat. Add the vegetable mixture and stir to combine. In another saucepan over low heat, add the milk and condensed cream of mushroom soup and simmer until heated through. Add the milk mixture, the frozen peas and the chicken to the vegetable mixture and simmer for about 5 minutes.
Arrange the biscuits on serving plates, then spoon the chicken mixture over the biscuits and serve.
If the dough appears dry, add more buttermilk. If you would like biscuits to have soft sides, have the disks touching each other. If you like crispy crusts, arrange them 1-inch apart. If the sauce is too thick, add a little milk to thin.
This recipe was provided by a chef, restaurant or culinary professional. It has not been tested for home use.
Recipe courtesy of Barry Keller, head chef, Earls Drive Inn, Chaffee, NY