Wash collards really well. Chop roughly.
Destem the leaves- fold in half and remove the center with a knife, or tear the leaves from the stem.
In a large pot, heat olive oil. Sauté onions until tender.
Add garlic and stir until fragrant.
Add broth and meat and bring to a boil.
Add collard greens, reduce heat to a simmer.
Cover and cook collard greens for 1-2 hours, checking and stirring. You want them soft, but not falling apart.
When done, add vinegar, and salt and pepper to taste. You can also add some red pepper flakes if desired.