02When the beef is falling-apart tender, remove it from the broth. Remove the thyme sprigs. Knead the butter and 2 tablespoons flour together until thoroughly combined. Add the mixture to the broth and stir with a wooden spoon until you have a sauce the consistency of buttermilk. Remove from the heat.03To serve, slice the beef and arrange on a platter. Cover with some of the sauce. Put the remaining sauce in a bowl or gravy boat. Arrange the carrots and celery attractively on the beef platter. Garnish with fresh thyme sprigs, if you like. Serve immediately.04Image courtesy of Jeffrey Allen.