From 1922:
Take half a pint of water, half a pint of cream, sugar, 4 eggs, ¼ lb. butter, ½ lb. flour, lemon or vanilla essence. Place the batter and cold water in a small clean saucepan and bring to the boil. Have ready the flour, and when the water boils stir this in quickly and beat till quite smooth; cook for a few minutes, and then turn into a basin to cool a little; break in the eggs one at a time, and beat for a few minutes after the last is in. Have ready a greased baking sheet, place the mixture in spoonfuls on the tin, taking care they are not too close, as they rise and swell very much; bake in a moderate oven for half an hour. Be very careful to avoid banging the oven door while they are baking, and avoid opening it if possible until just before the half-hour expires; then you take them out, make an opening in the top of each cake, and fill with cream (which should be whipped while the cakes are baking) and sweetened and flavored to taste.