If using whole chicken breasts, cut into 1" dice. Follow same instructions as diced chicken.
If using shrimp, follow same instruction as chicken in Step 1 and 2, searing shrimp until they reach minimum internal temperature, 2-3 minutes per side. Add shrimp to chowder at the end of Step 4 and stir until shrimp are heated through, 1-2 minutes.
If using Italian sausage, remove from casing and do not season. Follow same instructions as chicken in Steps 2 and 4