Preheat your oven to 375°F (190°C) and coat a 13x9-inch baking dish with nonstick spray.

In a large mixing bowl, combine the cooked, shredded chicken, cream of chicken soup, thawed mixed vegetables, minced garlic, and black pepper. Stir in the cheeses until evenly coated.

Transfer the chicken mixture into the prepared baking dish, spreading it evenly.

Cut the canned biscuits into quarters, place in a bowl, and drizzle melted butter over them, tossing to coat.

Arrange the biscuit pieces over the chicken filling in a single layer.

Bake uncovered for 35 to 40 minutes until the biscuits are golden brown and the filling is bubbly.

Allow to cool for a few minutes before serving.