In a 3 1/2- or 4-quart slow cooker, combine sour cream, shredded provolone, mayonnaise, cream cheese and scallions – stir to combine. Place lid on slow cooker and cook on low for 3-4 hours or high for 1 1/2-2 hours.
Just before serving, stir in salami and ham. Top with pepperoncini and cherry tomatoes.