Using buttermilk baking mix, add enough water to make dough. Roll into rectangle.
Spread with soft butter. Sprinkle sugar and cinnamon over the buttered dough. Cover
with cut-up rhubarb and roll up like a jellyroll; slice. Place slices in greased
baking pan and pour hot syrup over all.
Bake at 425 degrees F for 25 minutes.
Top with vanilla ice cream or whipped cream while warm.
Syrup: Bring sugar and water to a boil for 5 minutes.