Rach's Chicken and Shrimp Pasta, Chesapeake Bay Style!

Name: Rach's Chicken and Shrimp Pasta, Chesapeake Bay Style!
Cuisine: American, Southern
Ingredients: 1 ½ pounds large; sweet-smelling pink shrimp; peeled and deveined; tails on; Juice of ½ lemon; 2 cloves garlic; chopped; 3 tablespoons seafood seasoning (Rach likes J.O. Spice Company's); 3 tablespoons EVOO; 1 pound pulled rotisserie chicken or 1 pound poached chicken; 3 tablespoons chicken seasoning (Rach likes J.O. Spice Company's); 3 tablespoons butter; 1 onion or 2 shallots; finely chopped; 1 small mild pepper; seeded and finely chopped; 1 rib celery with leafy tops; 1 large bay leaf; 4 cloves garlic; Salt and pepper; 2 tablespoons flour; Splash of dry sherry or white wine; 2 cups chicken bone broth or stock; 1 cup heavy cream; 1 pound penne rigate; 1 cup grated Parmigiano-Reggiano (optional); Cayenne pepper sauce; to taste; Chives (a small bundle)