Prepare one pint of butter sauce. Meanwhile put one pound of green gooseberries into a small copper saucepan containing boiling water. Boil for five minutes, then drain the gooseberries, and put them in a little stewpan with one-half pint of white wine and three ounces of powdered sugar. Cook gently the gooseberries, rub them through a sieve, and add the resulting pulp to the butter sauce. Excellent with grilled mackerel and the poached fillets of that fish.