Remove the fat and skin from the kidneys, slice them and cut in small pieces. Cook on a brisk fire in a little lard, seasoning with salt and pepper. In 3 to 4 minutes remove from the pan and drain on a colander. Put the sherry in a frying pan and reduce by half. Then add to it 1 or 2 tablespoons of Espagnole sauce, and cook the kidneys in this sauce for a few minutes. Put on a hot dish, sprinkle with chopped parsley, and garnish with the croûtons.