In large pot bring broth to boil. Add all seasonings and veggies. Place pork in liquid and reduce heat to simmer. Simmer 2-3 hrs till it shreds with a fork.
Remove pork from liquid and shred. Remove the onions from liquid. Put shredded pork in casserole dish and add the onions. Add bacon grease or butter to pork and about 3 cups of the simmering liquid, mix well.
Roast at 425°F for about 20 minutes stirring once. Pork should be sizzling and slightly browned.