Heat a little olive oil in a skillet over medium heat, maybe a tablespoon or so. Add the potato and let it cook, without stirring, for several minutes until it starts to brown. Stir, and add the onion, green pepper, garlic and thyme. Let the vegetables sit untouched for several minutes so that the potatoes continue to get brown, then stir every few minutes. Once the potatoes are brown and the onion and pepper are soft, add the turkey. Stir it all together, then add the leftover gravy or butter. Stir to melt the gravy or butter and coat the turkey and vegetables. Season with salt and pepper.