Original Receipt in 'A Shilling Cookery for The People' by Alexis Soyer (Soyer 1845);425. Mustard Sauce.- Put in a stew pan four tablespoonfuls ot chopped onions (No. 449), with half an ounce of butter, put on the fire and stir till it gets rather hot, add half a teaspoonful of flour, mixed well, also half a pint of milk or broth (No. 1); let the whole boil ten minutes, season with half a teaspoonful of salt, a quarter that of pepper, a little sugar, and two teaspoonfuls of French or English mustard; when it boils it is ready.
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Mustard