Heat your griddle to medium heat and add the bacon. Cook for 5-6 minutes or until crisp and fully cooked. Remove from the griddle and drain on a few pieces of paper towel.
Add the onion to the griddle and cook for 4-5 minutes, tossing often.
Add the collard greens with a pinch of salt, a large pinch of pepper and toss to incorporate. Cook for 4-5 minutes, tossing often.
Add ½ of the chicken stock and cover with a dome. Cook for 3-4 minutes.
Add the remaining chicken stock, red wine vinegar and red pepper flake. Toss to evenly combine ingredients. Cover and cook for another 4-5 minutes then serve hot.
