Put into a stewpan four good handfuls of sorrel (after being well
washed,) with a small piece of butter, put on the cover and set it over
a moderate fire without water, until melted; then put it on a sieve, and
rub it all through; put half a tablespoonful of very fine chopped
onions, and two ounces of butter into a stewpan, pass them over a quick
fire two or three minutes, add a tablespoonful of flour, mix well
together, add the sorrel and ten tablespoonfuls of broth (No. 133), half
a teaspoonful of sugar, a little salt and white pepper; let it boil
fifteen minutes, stir in two yolks of eggs quickly, and it is ready to
serve. Demi-glace (No. 9) is very good instead of broth.