Turkey Breast Roulade with Sous Vide Porcini

During a good porcini year, I dehydrate at least half my hoard. This is a recipe that takes advantage of that stash. Half of this recipe—the turkey roulade—comes from the New York Times adaptation of an Ina Garten recipe. The other half—sous vide porcini—is my own invention. Sous vide is an extraordinary method for extracting maximum flavor from mushrooms: A fistful of dried porcini in a pint jar of heavy cream submerged in a sous vide device’s water bath, or simply placed in a low-t