Preheat oven to 350 degrees. Coat a 13 x 9-inch baking dish with cooking spray and set aside.
In a large pan, add 2¾ cups chicken broth, butternut squash, potatoes, onions, carrots, celery, and garlic. Bring to a boil over medium-high heat. Reduce heat, cover, and simmer for 8 minutes, until soft. Add diced turkey and frozen peas, breaking them up. Bring back to a boil, turn heat to simmer, cover, and cook for 5 minutes. Place a colander into a large bowl. Pour turkey, vegetables, and broth into the colander. Add the strained broth back to the pan. Set aside the bowl of turkey and vegetables.
In a separate small bowl, add flour. Gradually add milk to flour, stirring with a whisk, until well blended.
Increase heat to the pan of broth to medium and stir in remaining broth. Using a whisk or fork, stir in milk and flour mixture. Cook for 5 minutes or until thickened. Stir often.
Add back the turkey and vegetables. Mix in thyme, sage, and black pepper. Mix well. Pour turkey stew into the 13 x 9-inch baking dish. Cover with foil and bake for 15 minutes. Remove from oven and remove foil.
Open the package of biscuits, separate them, and place them on top of turkey stew. Line them evenly over the top.
Place the pot pie back in the oven and bake, uncovered, for 14-16 more minutes until the biscuits are golden brown.
To serve: spoon about 1 cup into each bowl and top with 1 biscuit. You’ll have 2 extra biscuits!