For the potato gumbo: Heat 1 tablespoon vegetable oil in a large high-sided saute pan over medium heat. Add the onions and saute until golden brown. Add the garlic and smoked bacon and continue to saute. Once the bacon has cooked and becomes crisp, add the celery, Swiss chard stems, and green pepper, saute until tender. Remove the bacon mixture from the pan, put in a bowl and set aside. Heat the remaining vegetable oil in the same saute pan, add the flour and bay leaves. Stir with a wooden spoon incorporating the flour and oil to form a paste. Cook until the flour becomes brown and nutty in color. Add the chicken stock, water, and cayenne, stir. Add the potatoes and reserved bacon mixture to the liquid. Cook over medium heat until the potatoes are tender and the liquid reduces, achieving a thick consistency, approximately 30 minutes. Add the Swiss chard leaves, season with salt, and pepper, cooking until the leaves are wilted, serving.