I don't believe I actually found this, but I did.  Actual Who Pudding, from Cindy Lou.

Here is the link, but I will copy it below if it doesn't work. Have fun!

http://www.seussville.com/titles/grinch/recipe.html

Who Pudding

At Christmastime, my favorite treat
 is something creamy, light, and sweet.
 "Who Pudding a la Cindy-Lou!"
 And here's the recipe for you.

2/3 cup long-grain (not converted) rice
 3 cups milk
 3/4 cup sugar
 1 teaspoon vanilla extract
 2 tablespoons butter
 1/2 teaspoon salt
 4 eggs, separated
 1/8 cup of red and green M&M;'s

Utensils needed:

double boiler, medium-size mixing bowls, small-size  mixing bowl, wire whisk, deep serving dish.

    1     With the help of an adult, combine rice and milk in  top of double boiler. Cover and cook over simmering water for 30 minutes or until rice is tender.

 
    2     Preheat oven to 325º F. Beat egg yolks with a  wire whisk until frothy. Stir 3/4 cup sugar, vanilla,  butter, salt, and egg yolks into warm rice mixture. Mix  well.

 
    3     Grease a shallow baking dish. Pour in pudding. Bake  for 35-40 minutes.

 
    4     Remove from oven and let cool on a wire rack for 10  minutes.

 
    5     Refrigerate overnight or for at least 8 hours. Top  with red and green M&M;'s before serving.

Feeds two hundred Whos . . . or four to six  yous.

 
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