Spring Veal Stew

Ingredients

• 3 lb. boneless veal shank or shoulder, cut into 2-inch cubes
• Salt
• freshly ground pepper
• 3 Tbs. unsalted butter
• 3 Tbs. olive oil
• 2 leeks, white and pale green portions, halved, rinsed and thinly sliced
• 1 cup dry white wine
• 2 fresh thyme sprigs
• 1/2 lb. asparagus, tough ends removed and spears coarsely chopped
• 6 oz. button or cremini mushrooms, sliced
• 1/2 lb. frozen peas
• 1/2 cup crème fraîche or sour cream
• 3 Tbs. chopped fresh flat-leaf parsley