Heat chicken and hot pepper sauce in a skillet over medium heat until heated through, 3 to 5 minutes. Stir in cream cheese and ranch dressing. Cook and stir until well blended and warm, 3 to 5 minutes.
Mix in 1/2 of the Cheddar cheese, and transfer the mixture to a slow cooker. Sprinkle the remaining cheese over top.
Cover and cook on Low until dip is hot and bubbly, about 35 minutes.