B.londe Shallot Marmalade

We do a similar thing at tavern and made me remeber this recipee for a very good shallot addition to a fish or even meat.
4 quarts diced shallots
1 quart lean veal scrap
3 quart Light veal stock
1/2 cup sherry vinegar
1 bottle of sweet dessert wine
1/2 bottle dry white wine
1/2 cup sugar
1 medium rondo
kuzu to thicken
bouqet garni