Preheat the oven to 400°F (200°C). In a large saucepan, melt the butter over medium heat. Stir in the flour and cook for 1-2 minutes until lightly golden.
Gradually whisk in the heavy cream and broth, stirring constantly until the mixture thickens, about 3-5 minutes.
Add the garlic powder, onion powder, Old Bay seasoning, salt, and pepper. Stir in the seafood and mixed vegetables until well combined. Remove from heat.
Pour the seafood mixture into a greased 9-inch pie dish or oven-safe skillet.
Open the biscuit dough and separate the biscuits. Place them on top of the seafood mixture, slightly overlapping them.
Brush the tops of the biscuits with the beaten egg for a golden finish.
Bake in the preheated oven for 20-25 minutes, or until the biscuits are golden brown and cooked through.
Let cool for 5 minutes before serving.