Preheat oven to 400°F (200°C) and grease a 9×13-inch baking dish.
Cook seafood in a skillet over medium heat for 3–4 minutes until shrimp turns pink. Set aside.
Make sauce in the same skillet. Add broth, cream, garlic powder, onion powder, thyme, salt, and pepper. Simmer for 5 minutes.
Add vegetables and cooked seafood to the sauce. Stir and simmer for another 5–6 minutes until slightly thickened.
Mix biscuit dough: Combine biscuit mix and milk in a bowl. Stir until just combined.
Assemble pot pie: Pour seafood mixture into the baking dish. Drop spoonfuls of biscuit dough over the top.
Drizzle butter over biscuits.
Bake uncovered for 25–30 minutes until biscuit topping is golden and cooked through.
Cool 5–10 minutes before serving.