Preheat oven to 375 degrees.
In a small saucepan, heat the chicken stock and dissolve the bouillon cubes in the stock. In a large pot , melt the butter and saute the onions over medium-low heat for 10 to 15 minutes, until translucent. Add the carrots and mushrooms and saute 5 minutes. Add the flour and cook over low heat, stirring constantly, for 2 minutes. Add the hot chicken stock to the sauce. Simmer over low heat for 1 more minute, stirring, until thick. Add 2 teaspoons salt, 1/2 teaspoon pepper, and the milk. Add the cubed turkey, carrots, peas, onions, and parsley. Mix well. Place the stew in a 10 x 13 x 2-inch oval or rectangular baking dish. Place the baking dish on a sheet pan lined with parchment or wax paper. Bake for 15 minutes.
With a rolling pin, roll out to 3/8-inch thick. Cut out twelve circles with a 2 1/2-inch round cutter.
Remove the stew from the oven and arrange the biscuits on top of the filling. Return the dish to the oven. Bake for another 20 to 30 minutes, until the biscuits are brown and the stew is bubbly.