In a large pot over medium-low heat, add 3 tbsp of butter. Once hot, toss in the shrimp and lobster meat. Cook for 3–4 minutes, then remove and set aside.
Add the shallot, carrots, celery, thyme, and cayenne pepper to the pot. Sauté for 3–4 minutes. Stir in the garlic and cook for an additional 2 minutes.
Add the tomato paste and flour to the pot, stir to form a paste.
Toss in the peas, corn and pour in the stock. Mix to combine, and let it simmer for 15 minutes.
While the filling simmers, prepare the biscuits and the biscuit butter. (these instructions are on the box)
Preheat the oven to 375°F.
To the pot add the heavy cream and seafood (cooked and crab) to the pot and divide the filling evenly into four ½-quart ramekins or cocottes, filling each about three-quarters full.
Top with a thin layer (1/4-1/3 cup) of cheddar bay biscuit dough. Either use wet hands to form a layer or press it between 2 pieces of parchment paper.
Bake for 15–17 minutes, or until the tops are golden brown. Brush with biscuit butter and serve.