In a bowl, gently combine the crab, scallion, serrano pepper, mayonnaise, hot sauce, lime juice and Old Bay Seasonings. Taste and season with additional salt and pepper. Refrigerate the crab mixture for 30 minutes.
Spoon half of the crab mixture into each of the avocado halves. Sprinkle with a dash of Old Bay Seasonings and top with chives. Enjoy!