Preheat the oven to 400 degrees F.

Cook the sausage in a large, heavy pot over medium heat for 5 minutes. Add 1 cup of the onions, the bay leaves, thyme and parsley. Season with salt and black pepper. Cook, stirring, until the onions are soft and lightly golden, about 5 minutes. Add the chicken stock, peas and 1 tablespoon of the garlic. Bring to a boil and cook, until the peas are tender, 1 1/2 hours. Cook the bacon in a large skillet over medium heat until crispy, 6 to 8 minutes. Add the remaining onions and the celery. Season with black pepper. Cook, stirring, for 3 minutes. Add the oysters and season with Essence. Cook for 1 minute. Remove from the heat and transfer the mixture to a mixing bowl. Add the cornbread and the reserved oyster liquor. Add the remaining tablespoon of garlic and enough water to moisten the dressing. Stir in the green onions. Season with Essence and cool completely. Season the tenderloin with Essence. Spread the dressing evenly over the tenderloin. Roll the tenderloin up tightly and tie with butcher's twine to secure the filling. Place the tenderloin in a baking pan lined with parchment paper. Brush the tenderloin with the cane syrup and roast, basting every 10 minutes with the remainig syrup, for 35 to 40 minutes for medium. Remove from the oven and cool for 5 minutes before slicing. To serve, spoon the black-eyed peas in the center of each plate. Slice the pork into individual slices and fan around the peas. Garnish with the sweet potato nests.