Make the Seafood Filling:

In a large skillet or Dutch oven over medium heat, melt butter and olive oil. Add onion, garlic, carrots, and celery. Sauté until softened, about 5–6 minutes.

Sprinkle in the flour and cook, stirring constantly, for 1–2 minutes to remove the raw flour taste.

Slowly whisk in the seafood stock, then the heavy cream. Stir until thickened, about 3–4 minutes.

Add Old Bay, salt, pepper, thyme, and peas. Stir in cooked shrimp and crab. Remove from heat and pour into a greased 9×13-inch baking dish or large oven-safe skillet.

Make the Biscuit Dough:

In a large bowl, whisk together flour, baking powder, baking soda, salt, garlic powder, and cayenne.

Cut in the cold butter using a pastry cutter or your fingers until pea-sized crumbs form.

Stir in cheddar cheese. Add buttermilk and mix just until combined—do not overmix.

Drop 8–10 spoonfuls of biscuit dough on top of the seafood mixture, spaced evenly.

Bake the Pot Pie:

Preheat oven to 400°F (200°C).

Bake uncovered for 25–30 minutes or until the biscuits are golden brown and the filling is bubbling.

Add Garlic Butter (Optional):

Mix melted butter with garlic powder and parsley. Brush over the warm biscuits immediately after baking for extra flavor.

Serve:

Let rest for 5–10 minutes before serving.