Preheat oven to 400F; grease a 9 by 13-inch casserole dish with shortening.
Add 3 tablespoons oil to a 5-quart pot over medium-high to high heat. Season the chicken with 1 teaspoon salt and 1/4 teaspoon black pepper; add the chicken to the hot pot and cook until browned on the outside, about 5 minutes (it will still be pink in the center, but it will finish cooking later). Transfer the chicken to a bowl and set aside.
Turn the heat down to medium; to the same pot, add the sweet potato and cook (covered) for 5 minutes, stirring occasionally.
Add the carrot, celery, onion, remaining 1 tablespoon oil, remaining 3/4 teaspoon salt, and remaining 1/4 teaspoon black pepper. Cover the pot and cook until the veggies start to get tender, about 6 to 8 minutes.
Add the garlic, thyme, bay leaf, and flour, and cook 1 to 2 minutes more, stirring constantly.
Stir in the white wine (or chicken stock) and use a wooden spoon to scrape up any brown bits that have formed on the bottom of the pot. Cook until the liquid is evaporated, about 30 seconds to 1 minute, stirring constantly.
Add the milk, Worcestershire sauce, Dijon, smoked paprika, and browned chicken, and stir until the sauce is lump-free. Turn the heat down to medium-low, cover the pot, and bring to a simmer, stirring occasionally.
Add the cheddar shreds and stir until they’re completely melted; turn off the heat and stir in the corn and peas. Remove and discard the bay leaf. Pour the cheesy chicken stew mixture into the prepared casserole dish.
For the biscuit topping, whisk together the flour, thyme, baking powder, and salt in a medium bowl. Use a fork to cut the shortening into the flour mixture (do not completely combine the shortening and flour; there should be some larger pieces about the size of peas). Stir the milk into the flour/shortening mixture with a wooden spoon, being careful not to over-mix.
Drop the biscuit dough out onto the top of the cheesy chicken stew mixture, leaving about 2 inches between each (I used a 2 tablespoon-sized scoop and I got 15 biscuits).
Bake (uncovered) until the biscuits are puffed and golden in places, and a wooden pick inserted into the center of a biscuit comes out clean, about 25 minutes.
Let the casserole sit for 10 minutes before serving.Recipe by: Faith Gorsky, Edible Mosaic