Fill a large stockpot with enough water to cover all ingredients.
Squeeze lemon halves into the water, then add the lemons to the pot.
Add garlic, bay leaves, Old Bay seasoning, paprika, cayenne pepper, salt, and black pepper. Bring water to a boil.
Add potatoes to the boiling water and simmer for about 10 minutes.
Add onions and corn, continue boiling for 5 to 7 minutes until vegetables are tender.
Add sliced sausage and optional proteins such as shrimp, crab, or chicken pieces.
Boil until shrimp is pink and opaque (3-5 minutes) or until crab and chicken are fully cooked.
Taste and adjust seasoning if needed.
Drain the water, then transfer the boil to a large serving platter or a table lined with parchment paper for communal serving.
Optionally, sprinkle additional Old Bay seasoning or chopped parsley for garnish. Serve with melted butter and lemon wedges.