<<Disclaimer: Verify this information before applying it to your situation.>>

I asked for a recipe for a GF sheet cake that is also nut free.  Here are 
the responses I received.  Please be aware that not all the recipes I 
received are nut free.
Thanks to everyone who replied.
Clare
Arlington, WA
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Either go to Julia Child's books and use cornstarch in place of wheat
flour...her suggestion, btw, or www.epicurious.com...a gourmet magazine
source.
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This is our all time favorite...It's actually better as leftovers, if it 
lasts that long!

Whipped Cream Cake

Preheat oven to 350º
         Grease an 8x12 inch pan.  Sift dry ingredients:
   1 1/2 c. oriental rice flour (a must!) *
         2 tsp. gluten-free baking powder
      1/4 tsp. salt
Whip until stiff:
         1 c. cold whipping cream
Add:  2 eggs
         1 c. sugar
         1 tsp. g.f. vanilla

Continue beating until no longer gritty.  Add dry ingredients, blend in with 
wire whisk.  Pour into prepared pan.  Tap on counter to remove air bubbles. 
Bake for 30-45 min, or until it tests done.  Top with cinnamon sugar while 
still warm or cool well & frost.  Make a double recipe in a 9x13" pan. 
(from The Joy of Gluten-Free Cooking,  Juanita Kisslinger)

* oriental rice flour is white rice (as opposed to sweet rice) flour made in 
Thailand...Typically sold in oriental stores. Unlike more non-brown rice 
flour, it is very finely milled.
-------------------------------
The Gluten Free Pantry cake and cookie mix is a good white cake.
You can also try using your favorite white cake recipe and substituting corn
starch one-for-one with the flour called for in the recipe.  I tried that
with cookies in December and it worked just fine.  I used Solo brand raspberry filling
between the layers and a cream cheese frosting.
-----------------------
White Texas Sheet Cake
(adapted from a Taste of Home Cook Book)

Cake:
1 cup butter
1 cup water
2 cups GF flour mix
2 cups sugar
2 eggs beaten
1/2 cup GF sour cream
1 teaspoon GF almond extract
1 teaspoon salt
1 teaspoon baking soda
1/4 teaspoon baking powder
2 teaspoons xanthan gum

Frosting:
1/2 cup butter
1/4 cup milk
4 1/2 cups powered sugar
1/2 teaspoon almond extract

In a large saucepan, bring butter and water to a boil.  Remove from heat; 
wisk in remaining cake ingredients until smooth.  Pour into greased 15 x 10 
x 1 inch baking pan (jelly roll pan).

Bake at 375 deg F. for 20-22 minutes or until cake is golden brown and tests 
done.  Cool for 20 minutes.

Meanwhile, for frosting, combine milk and butter in a medium saucepan and 
bring to a boil.  Remove from heat.  Add sugar and almond extract.  Mix 
well.  Spread over warm cake.
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I use Gluten Free Pantry Old Fashioned Cake and Cookie mix.  It is gf and
nut free.  We have both celiac and nut allergy (extended family) and
have used it often without any problems.
---------------
-----------------------
MOCHA BARS - Mary Iverson

Sylvan’s lemon cake mix
3 oz pkg Jello instant pudding
  (coconut cream)
2 eggs
2 c milk

Mix well and put in greased jelly roll pan. Bake at 350 for 20-25 min.

Frosting

1 1/2 sticks butter, melted
3 c powdered sugar, sifted
1 tsp vanilla
1 tbsp milk if needed

Spread on bars gently. Cover with chopped peanuts and pat into frosting.

Of course, you may omit the nuts in either recipe or use different 
frostings. I enjoy both these recipes.
----------------------
I am a baker..ran the coffee hour for a very large NYC church. I made gf
cakes all the time.  Best I found was Julia Child's recipes and followed her
advice. She said, in the French Chef, to use cornstarch, cup for cup for
cake flour. I checked with a prof baker who said you could also use it for
reg flour.  I've been doing it for years. You get a nice, light, delicate
cake. You get a heavy, dense gritty cake with gf flour mixes and the bean
mixes really taste gross.

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