Substitute for Verjus?
I'm planning to make Suzanne Goin's Pancetta Wrapped Trout this weekend which is accompanied by a verjus sauce. It seems there must be some mysterious run on verjus in my city because all the stores I've called are out of stock.
The recipe calls for the verjus to be simmered along with some red grapes and shallots, then pureed with cold butter and lemon juice.
Can anyone suggest a substitute? I won't have time to mail order!