It is a yellow sauce made of white butter sauce with yolks of eggs stirred in to color, and speckled with minced truffles, mushrooms, shalots and white pepper. Add a spoonful of white wine or little dash of lemon juice. A very small quantity of such a sauce can be made to fill the bill and one small truffle out of a bottle and four or five mushrooms sliced will be all that are needed. Trianon is the name of a place - a French palace.