Put butter and water in saucepan and place on front of range. As soon as boiling point is reached, add flour all at once, and stir vigorously. Remove from fire as soon as mixed, and add unbeaten eggs one at a time, beating, until thoroughly mixed, between the addition of eggs. Drop by spoonfuls on a buttered sheet, one and one-half inches apart, shaping with handle of spoon as nearly circular as possible, having mixture slightly piled in centre. Bake thirty minutes in a moderate oven. With a sharp knife make a cut in each large enough to admit of Cream Filling. This recipe makes eighteen small cream cakes. For flavoring cream filling use lemon extract. If cream cakes are removed from oven before being thoroughly cooked, they will fall. If in doubt, take one from oven, and if it does not fall, this is sufficient proof that others are cooked.