Rub down into a saucepan one ounce of butter with a dessertspoonful of flour.

When the butter and flour are in a cream, mix with the juice of the vegetables out of the paper bag, to which half a gill of water or milk should be added. Salt and pepper to taste. Stir till the sauce is thick; then add half an ounce of proteid food, well stirred in, and pour the sauce over the vegetable, or serve it in a sauce-boat.