Map<String, List<Map<String, Object>>> yourMap = ...;
//iterate over outer map
for(Map.Entry<String, List<Map<String, Object>>> topEntry : yourMap) {
  String topKey = topEntry.getKey();
  //iterate over list
  for(Map<String, Object> innerMap : topEntry.getValue()) {
    //iterate over inner map
    for(Map.Entry<String, Object> innerEntry : innerMap) {
      String innerKey = innerEntry.getKey();
      Object innerValue = innerEntry.getValue();
    }
  }
}