Thinly slice the carrot and onion. Melt the dripping and in it slowly fry the onion and carrot until they are golden brown. Stir in the flour and fry it even more slowly till it is also golden brown. Stir in the stock, bring to simmering point, season then simmer for ½ hr. Strain the sauce before use. As the frying of the flour is a long process, extra colour may be given to the sauce by adding a piece of brown onion skin, or a little gravy browning or a little meat or vegetable extract which will also add to the flavour.