Follow these steps to create your Southern Collard Green Potato Stew perfectly:

1. Prep the Ingredients: Wash and chop collard greens, peel and dice the potatoes, chop the onion, and mince the garlic.
2. Sauté Vegetables: In a large pot, heat olive oil over medium heat. Add the chopped onion and garlic and sauté until soft and fragrant, about 2-3 minutes.
3. Add Broth: Pour in the vegetable or chicken broth and bring to a gentle boil.
4. Mix in Potatoes: Once boiling, add the diced potatoes and stir well. Cook for about 10 minutes until the potatoes begin to soften.
5. Incorporate Collard Greens: Add the chopped collard greens to the pot and mix until they wilt.
6. Season the Stew: Sprinkle in the smoked paprika, cayenne pepper (if using), salt, and black pepper. Stir well to combine all ingredients.
7. Simmer: Reduce the heat and let the stew simmer for an additional 20-25 minutes until the potatoes are tender and flavors have melded together.
8. Finish with Vinegar: Stir in the apple cider vinegar just before serving to enhance the flavors.
9. Garnish: Serve the stew hot and garnish with fresh thyme or parsley if desired.

Thoroughly following these steps will ensure your Southern Collard Green Potato Stew is full of flavor and heartiness.