Melt the butter in a large flameproof casserole or dutch oven and brown the hare, turning frequently, over a moderate heat. Place the ham steak in the bottom of the casserole and sprinkle the shallots over the meat. Cook for 5 minutes, stirring frequently. Season with freshly ground black pepper. Add the white wine vinegar and 3 tablespoons of white wine. Simmer for 1 1/4 hours, stirring occasionally, and adding more wine if the meat seems dry. Remove the hare from the pan and keep warm. Strain the cooking liquid and return it to the pan. Stir in the crÅme fraöche and boil until thickened. Mix the cornstarch with 2 tablespoons of the sauce and stir it back into the sauce. Boil until thickened. Spoon the sauce over the hare and serve immediately.
