Preheat your oven to 400°F (200°C) and lightly grease a 12-cup muffin pan with cooking spray or butter.
In a large mixing bowl, combine the cream of chicken soup, cooked chicken, and frozen mixed vegetables. Stir until everything is well combined. Season the mixture with salt and pepper to taste.
Open the cans of flaky biscuits and separate the dough. Flatten each biscuit using your hands or a rolling pin. Press each flattened biscuit into the muffin pan cups, ensuring to push the dough up the sides to create a cup.
Spoon the chicken and vegetable mixture into each biscuit cup, filling them generously.
Place the muffin pan in the preheated oven and bake for 18-20 minutes, or until the edges of the biscuits are golden brown and the filling is heated through.
Once baked, allow the biscuit cups to cool for a few minutes in the pan before carefully removing them. Serve warm and enjoy!