Place rhubarb in a 9x6x2-inch baking dish or 9-inch round layer cake pan. Combine sugar, flour, orange rind, orange and lemon juices, and water; pour over the rhubarb. Place in oven at 400° and heat for 5 minutes.
Meanwhile, if using biscuit dough, cut out into 2-inch rounds. Place biscuits over hot rhubarb mixture; lightly brush with evaporated milk or milk. Mix chopped walnuts with the granulated sugar and cinnamon; sprinkle over biscuits. Bake for about 30 minutes. Serve rhubarb cobbler warm. Serve with ice cream, if desired.
Calories per serving: 270