Coat the pork tenderloin slices with flour and shake off the excess. Melt butter in a large frypan over medium-high heat. Cook the tenderloin in the hot butter until golden brown on both sides and no longer pink in the centre, about 5 minutes. Remove to a platter and keep warm.
Pour the vermouth into the frypan and bring to a simmer; cook for 1 minute. Add the chicken stock and lime juice. Cook and stir until reduced by about half. Stir in the cream, yellow mustard, honey mustard and allspice. Pour the sauce over the pork to serve.