Directions In a bowl, beat egg. Add brown sugar, buttermilk, oil and vanilla; beat for 1 minute. Combine dry ingredients; stir into sugar mixture just until moistened. Fold in rhubarb and walnuts. Fill greased or paper-lined muffin cups three-fourths full. Combine topping ingredients; sprinkle over muffins. Bake at 375degrees for 20-25 minutes or until muffins test done. Yield: 1 dozen. Originally published as Rhubarb Muffins in Country Woman March/April 1997, p32