— au gratin.—Blanch the onions as above, then finish cooking them in milk and water till tender enough to sieve (or if preferred to mash), mix them with a little of the liquid they were cooked in, a spoonful or two of cream, and a seasoning of salt, white pepper, and a little cayenne; pour this purée into a well buttered piedish (or shells, as you please) previously dusted with breadcrumbs, grated cheese, and seasoning, cover the top with the crumbs, cheese, seasoning, and a few drops of liquefied butter, and set in the oven for a few minutes till the top colours nicely. Another form of this dish is to slice down some cold cooked onions (they should be rather undercooked) and arrange them alternately with peeled and sliced tomatoes, in a dish prepared as before, and finish off as in the previous recipe.