Melt 2 Tbl of butter in the pan and sprinkle the flour in. Whisk the roux continuously until the rawness of the flour vanishes, about 1-2 minutes. Turn the heat to medium-low and add shallots, green onions and ham. Saute until soft. Break the flour/butter/aromatics combination down with the wine and beef stock by pouring in the liquids, gradually, and whisking constantly. Return the mushrooms to the pan. Add the cayenne pepper. Season to taste with salt and pepper. Reduce the sauce over medium heat until it coats the back of the spoon. Return the steak to the pan. Enrich the sauce with 1 Tbl of cold butter. Once the butter has been incorporated, cut off the heat.