Rhubarb is actually a vegetable and originated in China over 4,000 years ago. The deeper the red, the more flavorful the rhubarb stalks are likely to be. Medium-size stalks are generally more tender than large ones, which may be stringy.
Turn these bars into a decadent dessert. Serve larger squares on dessert plates drizzled with caramel sauce, then add soft whipped cream and an edible flower to dazzle guests.