Preheat and Prepare the Muffin Tin: Preheat the oven to 375°F (190°C) and grease a muffin tin.
Prepare the Dough: Roll out the biscuit or puff pastry dough into flat circles. Cut them to fit into the muffin tin.
Combine the Filling: In a bowl, mix shredded chicken, frozen peas and carrots, cream of chicken soup, milk, garlic powder, onion powder, salt, and pepper. If using, mix in cheese and herbs.
Fill and Seal: Place the dough circles into the muffin tin. Fill each with the chicken mixture and top with another circle of dough, pressing to seal.
Bake: Bake in the oven for about 20-25 minutes, or until golden brown.
Cool and Serve: Allow to cool for a few minutes before serving.