Preheat oven to 300 degrees. Butter dish. In a bowl, place the bread, 1 cup sugar, 4 egg yolks, 1 whole egg and milk; mix with your hands until well mixed and bread has turned into small lumps. Add raisins and vanilla and mix in well. Pour this mixture into previously buttered dish and bake in 300-degree oven until it just starts to brown lightly. Take out of the oven and sprinkle 1/4 cup of sugar over top of pudding and then pour the sherry over the sugar, return to oven, and continue baking until a fork comes out clean from the middle of the pudding. Let cool. Beat the 4 egg whites with a pinch of cream of tartar or a few drops of lime. Gradually add the remaining 1/4 cup of sugar, and continue beating until short, stiff peaks hold their shape. Once the pudding is at room temperature, spread the meringue on it and touch the surface lightly with a spatula, moving it up to form small peaks. Serve at room temperature. Leftovers can be stored in the refrigerator for up to a week; however, meringue will deflate, turning into a syrup that will mix with the sherry syrup. Since egg whites are raw, it must be refrigerated and should not be consumed after 1 week.