Place oil in a large pot over medium heat and add chopped onions. Cook and stir until softened, about 4-5 minutes. Add chopped garlic and stir for an additional minute.

Add smoked ham hocks, cajun seasoning, chicken broth, and black-eyed peas. Increase heat to medium-high heat and bring the mixture to a quick simmer. Allow to simmer for 2 minutes, then reduce heat to medium-low. Cover with a tightly fitting lid and allow to simmer on medium-low heat for about 1 hour, until the meat becomes tender. Remove the ham hocks from the pot and remove the meat from the bone. Set the meat aside.

Add roasted tomatoes and collard greens to the pot. Allow it to simmer for an additional 20 minutes until the greens are tender. Return the meat to the pot and add the apple cider vinegar. Salt and pepper to taste.