The recipe is one that I submited, it's called Rhubarb Pudding Dessert.
Yes, you'd want to double the entire recipe, if it's going to fit into a 13 X 9. You'll also probably have to bake it a little longer. Just keep an eye on it once it reaches the time recommended in the recipe--it probably won't take twice as long to cook, but will take maybe an extra 20-40 minutes or so, depending upon the recipe.
Callie is right. An 8x8 pan is 64 square inches and a 9x13 is 128 square inches. I figure 64x2=124 so I know that it will be a good fit when I double the recipe. You can figure the area of any pan and compare it to another to see if it will be 1 1/2 or double a recipe. No fun when a pan overflows!
Could you please post your rhubarb recipe, I would love to try the 8X8 version as I don't have very much rhubarb. Thanks
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