Wash and drain rice. Melt butter in large skillet. Add rice, almonds, onions and mushrooms. Cook and stir until almonds are golden brown, about 20 minutes.
Heat oven to 325F. Pour rice mixture into ungreased 1-1/2 qt. casserole. Heat chicken broth to boiling; stir into rice mixture. Cover tightly. Bake 1 1/2 hours or until all liquid is absorbed and rice is tender and fluffy.