In a large saute pan, over medium heat, melt the butter. Add the onions, celery and carrots. Season with salt and pepper. Saute for 4 to 6 minutes. Dust the vegetables with 2 tablespoons of the flour. Continue to cook for 2 minutes. Stir in the garlic and left-over vegetables. Season with salt and pepper. Stir in the stock. Add the turkey meat. Bring the liquid to a boil, reduce the heat to medium-low and simmer for 25 to 30 minutes. Remove from the heat. In a mixing bowl, combine the left-over potatoes, egg and flour. Add enough milk to make a thick batter. Season with salt and pepper. In another large saute pan, heat 1 tablespoon of the oil. When the oil is hot, drop the batter, 2 heaping tablespoons at a time, into the pan. Cook the cakes in batches. Cook until the cakes are golden on both sides. Repeat until all of the oil and batter is used. Drain the cakes on paper towels. Sprinkle with Essence. To serve, place two cakes in the center of each serving plate. Spoon the stew over the cakes. Garnish with parsley.