Place flat tortilla chips in a single layer on a large baking sheet.
In the bowl of a food processor, combine roast beef and next 3 ingredients. Process until mixture is smooth and well blended. Spoon mixture into a pastry bag fitted with a medium round pastry tip.
Pipe the beef mixture onto each tortilla chip in a cone shape. Press the top into pointed tip with your fingers. Repeat with remaining beef mixture and tortilla chips. Refrigerate for 1 hour.
Meanwhile, in a medium bowl, combine crushed rye chips and tortilla chips.
Gently press crumb mixture onto and around the tops of each witches hat, being careful not to press too hard. Refrigerate while preparing pepper rings.
For pepper rings, microwave pepper rings in a small amount of water for 1-2 minutes or until softened. Drain and cool pepper rings with cold water. Pat pepper rings dry and cut one side of each ring.
Place a pepper ring around the base of each withes hat. Refrigerate until ready to serve.