I made 5 1/2 jars of Rhubarb Jam and then used the crust recipe with a minor alteration (I used almonds instead of walnuts).
1 3/4 cups all-purpose flour
1 packed cup light brown sugar
1 teaspoon ground cinnamon
3/4 teaspoon fine sea salt
3/4 teaspoon baking soda
1 3/4 cups old-fashioned oats
1 cup (4 ounces) Slivered Almonds
1 cup (2 sticks) unsalted butter, melted
1 egg, at room temperature, beaten
1 teaspoon pure vanilla extract
Combine all of the dry ingredients, then add the melted butter, vanilla and egg. Place 1/2 of the mixture in the bottom of a greased 9X13 backing dish. Spread one 13 oz jar of Rhubarb Jam over the bottom crust and then sprinkle and press the other half of mixture on top. Cook at 350 for 30 minutes or until golden brown. Easy!!
I managed to get the jam and bars made, as well as getting about 5 cups of chopped rhubarb frozen. I'll probably get one more good harvest out of our plants. I could eat it all now, but I think it will be even better when in the chill of late fall or early winter I dig into my stocked freezer to find a little treat!