Combine all ingredients for the caramel in a pot. Cook without stirring until temperature reaches 240F. Remove the pot from heat then stir in the vanilla. Leave to cool for about 10 minutes.
Stick the apples onto wooden skewers and swirl in the caramel until evenly coated. Place the apples onto a silicon mat and leave for about an hour to allow the caramel to set.
Melt the chocolate in a double boiler. Take the apples and coat evenly with melted chocolate.
Sprinkle chopped Snickers over the chocolate shell and leave to set.