Sour-Sweet Rhubarb Pie A sour-sweet upside-down rhubarb pie is perfect in spring and summer when this unassuming and largely ignored plant explodes to life in forgotten corners of almost any garden. This post may contain affiliate links, which means I will receive a commission if you purchase through my links, at no extra cost to you. Please read the full disclosure for more information. Thank you! Rhubarb is a reddish stacks and green gigantic leaves vegetable the ancient civilisations used in medicine for its numerous health benefits. Although it has a sour taste and might require sugar to make it acceptable for...