Remove stems from greens and discard. Roll up like a cigar and slice into ribbons.
In a large pot over medium heat, add bacon, onion, and garlic. Render bacon until crisp and the onion is tender, about 6 minutes.
Stir in brown sugar, vinegar, broth, and bourbon. Season with salt and pepper. Bring to a simmer and stir in the collard greens in batches. Cover and cook for 1 1/2 hours until tender and soft.