This is an entirely delicious and new way of enjoying Rhubarb! The crust part tasted like a shortbread cookie, and the rhubarb topping was very similar to a Rhubarb Custard Pie filling. Go ahead, cut back the sugar, I used 2 1/2 cups, and that was fine for us. I used all the butter called for in the crust, and I think this was a good call, as shortbread *has* to have that really buttery flavor. I used frozen rhubarb, and that extended the baking time a good deal. Keep baking until that runny texture becomes a soft custard. Don't use a smaller pan as one person suggested, especially when using the frozen rhubarb, that made the baking time so much longer that the corners browned quite a bit. I think that adding a little more rhubarb could be a good thing, I think I will do that next time. Cut to serving size while still warm, so that the crust isn't brittle, and then allow to cool even more before serving. This allows the custard portion to firm up. Give this recipe a try, you won't be dissapointed!  -  23 Mar 2008  (Review from Allrecipes USA and Canada)

This was great! As others' suggested, I reduced the sugar to 2 cups (which was still very sweet) and baked it for an additional 10 minutes. One new suggestion is to spray the sides of the pan with oil. This will make for a lot easier clean up! The bottom does not need it because of the crust.  -  04 Jul 2006  (Review from Allrecipes USA and Canada)

Yum. I didn't think these would ever be done, but learned that they set and become firmer as they cooled (I cooked it 10 minutes longer as others had suggested and the middle was still runny, but took it out anyway so the crust didn't burn. It firmed up to bar-consistency as it cooled).  -  31 Jul 2006  (Review from Allrecipes USA and Canada)