Heat 2 T oil in a large saucepan until hot. Add 1 lb beef and brown on all sides. Remove with a slotted spoon and set aside. Repeat until all beef is browned.
Use additional oil as needed. Return all beef to saucepan. Add 4 cups of water, tomato paste, onions, celery salt, spices, herbs and green chiles; mix well.
Boil, then reduce heat to simmer, covered, for 90 minutes, stirring occasionally. Add remaining water.
Mix in chocolate; simmer, covered for 30 minutes, stirring often.
