Wash, break off ends and boil beans until tender. (Steam, if you prefer.) Season with sugar, salt and pepper while beans are cooking. Drain.
In a saucepan sauté the mushrooms until tender in the butter. When cooled somewhat add the flour and the cream. Cook over low heat, stirring often, until thickened. Remove from stove and add lemon juice.
Just before serving combine the beans with the mushroom sauce. Turn into a baking dish, sprinkle top with bread crumbs and almonds.
Reheat and serve at once.