If using shrimp, follow same instructions as scallops in Step 4, cooking undisturbed until seared on one side, 2-3 minutes. Flip, and cook until shrimp reaches minimum internal temperature, 1-2 minutes.
If using 16 oz. scallops, follow same instructions as 8 oz. scallops, seasoning with chimichurri seasoning and a pinch of salt and pepper. Cook in batches if necessary.
If using chicken, pat dry and cut into 1" dice. Season with chimichurri seasoning. Stir occasionally over medium heat until chicken reaches minimum internal temperature, 5-7 minutes.