If you have a large rhubarb harvest a great DoAhead is to dice and freeze extra quantities. Measure out what you need for your recipe (or any other recipe) and label the baggie accordingly. Prep time will be a breeze the next time you’re ready to whip up your dessert.
This dessert may also be made in it’s entirety and frozen prior to baking. It can go straight from the freezer to the oven as long as you have it in a foil pan.